自考英語(一)復習資料第十章
時間：
未知2
公共課
Text A Scientific Attitudes
搭配：
1. Seek answers to questions 尋找什么問題的答案（seek的過去式：sought）/動詞詞組
2. lay aside 擱置（lay的過去式：Laid）/動詞詞組
3. Be curious about 對什么好奇/形容詞詞組
4. Take apart （e.g. a watch） 拆散/動詞詞組
5. Combine sth. with sth. 把什么和什么結合在一起/動詞詞組
6. Carry out the experiment 完成試驗/動詞詞組
7. Belief in sth./sb. 相信某人或某事/名詞詞組
8. （there is）an explanation for sth. 解釋某事/名詞性詞組
9. There is a good reason why +句子 這就是為什么的原因
10. Not at all 一點也不/副此詞組
11. Regardless of 不管；無論/形容詞詞組
12. Succeed in sth./doing sth. 成工作某事/動詞詞組
13. The solutions to problems 問題的解決辦法/名詞的解決方法
14. In advance 提前/副詞詞組
15. Adapt sth. to sth. 使什么適應什么/動詞詞組
16. Make up one's mind 下定決心/動詞詞組
17. Once and for all 一勞永逸地/副詞詞組
18. Change in thinking 思想的轉變/名詞詞組
19. Make sth. necessary 事某事很必要/動詞詞組
20. In the light of sth. 根據，參照，考慮到/介詞詞組
21. Respect for sth. 對什么的尊敬/名詞詞組，動詞詞組
22. The difficulty comes up. 問題產生了
23. Base on sth. 根據什么/動詞詞組
24. It may take time for sth./sb. to do sth. 做某事花某人多長時間
25. Conditions for sth. 什么的條件/名詞詞組
語言點：
1. Belief的復數形式為beliefs
2. Well-known/著名的
3. Curious（adj.好奇的）——curiosity（n.好奇）；imagine（v.想象）-imagination（n.想象力）
4. Scientifically minded people 有科學頭腦的人
5. In cases where the explanation is unknown the scientific point of view is that there is a reason if it can only be discovered. 在對于現象還無法解釋的時候，科學的觀點是有理由相信遲早這種解釋是可以被發現的。
6. This means the ability to（做什么的能力） face the facts as they are（實事求是） regardless of what one has previously thought.
7. Agree（v.同意）-disagreeable（adj.令人討厭的）
8. The worker in science must face facts whether they are pleasant or unpleasant.
I didn't know whether to laugh or to cry when I heard the news.是…還是…
Whether he succeeds or fails， he has to do his best.
He doesn't know whether she is in Britain or she has gone to France.
9. Thomas Edison failed thousands of times before he succeeded in producing the first electric lamp.
10. Accept（v.接受）-acceptable（adj.可接受的）
11. Scientific truth offers an explanation that is acceptable only in the light of what is known at a particular time.
12. New ideas are frequently very slow to be accepted.
13. Continued progress 繼續的發展
14. 時態題：There is an experiment on the sprouting of seeds which has been running for more than 50 years.
Text B Solving Problems Scientifically
搭配：
1. Arouse one's curiosity 引起某人的注意/動詞詞組
2. Result from=arise from 由于/動詞詞組；result in 導致/動詞詞組
3. Give clue for doing sth. 為做某事提供線索/動詞詞組
4. Build a firm foundation for doing sth. 為做某事打下堅實的基礎/動詞詞組
5. Make an inference 做推論/動詞詞組
6. Turn out to be 結果是/動詞詞組
7. Check with 與什么相符/動詞詞組
語言點：
1. Once是連接詞，表示一旦。
2. A thoroughly understood problem is well started toward solution. Be well started toward 是什么的良好開端。
3. The development of industry has also brought about large numbers of problems which have to be solved.
4. Related questions 相關問題；unanswered questions 為回答的問題；controlled conditions 被控制的條件
5. Reliable（adj.可信賴的）-unreliable（adj.不可信賴的）
6. Should the observations or predictions turn out to be as expected， the scientist has added confidence in the probable truth of his hypothesis. = If the observations or predictions should turn out to be as expected， the scientist has added confidence in the probable truth of his hypothesis.
本課需要重點掌握的語法現象：動名詞
動名詞兼有動詞和名詞的特征。因此在句中可以做主語、表語、賓語和定語。
1．作主語
直接將動名詞放在句首作主語，謂語動詞用單數。
如：Seeing is believing. 百聞不如一見。
Swimming is the best exercise in summer.在夏天，游泳是最好的鍛煉方式。
注：a)動名詞和不定式都可以作主語，一般可以互換。但有時又略有區別。動名詞作主語往往表示一般或抽象的多次行為，不定式作主語表式具體的或一次性的動作。
如：Playing with fire is dangerous.（泛指玩火）
To play with fire will be dangerous.（指一具體動作）
b)在It is no use(good), not any use (good), useless 等后面一般用動名詞作主語。
如：It is no use arguing with him.同他爭論無用的。
It is no good learning English without practice.學英語不練是不行的。
2．作表語
如：The real problem is getting to know the difficulties of the students.現實的問題是了解學生的困難。
注：a)動名詞和不定式都可以做表語，區別在于：表示抽象的一般的行為時，多用動名詞；表示某次具體的動作或具有將來時的意義時，多用不定式。
如：My job is teaching English.我的工作是教英語。
My today's job is to teach you how to study English. 我今天的任務是教你如何學英語。
b) 動名詞作表語時不要與進行時態混淆。進行時態說明動作是由主語完成的。動名詞作表語，說明主語的性質和情況。
如：He is collecting stamps.他在集郵。（現在進行時）
His hobby is collecting stamps.他的愛好是集郵。（動名詞）
c) 動名詞和現在分詞作表語的區別：動名詞作表語說明主語的內容，而且可以轉換到句首作主語；現在分詞作表語，表示主語的特征，其作用相當于形容詞。
如：His favorite sport is running.他最喜愛的運動是跑步。
可以轉換為：Running is his favorite sport.
The film is very moving.這部影片很感人。
3．作賓語
1)必須接動名詞作賓語的動詞有：admit, appreciate, avoid, consider, delay, deny, finish, mind, postpone, risk等
如：We'd better postpone discussing it till next week.我們最好把這件事推遲到下星期討論。
2) 有些動詞既可以接動名詞也可以跟不定式作賓語。如：attempt, begin, continue, hate, like, love, start，need等。如果用動名詞，在意義上比較一般和抽象，時間觀念不強；如果用不定式則表示具體的動作，有將來時的含義。
如：The boys like playing football.這些男孩們喜歡踢足球。（經常性的動作）
Would you like to play football with us this Sunday? 這個周日愿意和我們一起踢球嗎？（指一次動作）
注：need, require, want作需要解時，后面須根動名詞或不定式的被動語態作賓語，這時動名詞的主動式表示被動的意義。
如：The window needs /wants/requires cleaning (to be cleaned).這個窗戶需要清洗。
3）在remember, forget, stop, mean, regret, try, go on等動詞后動名詞和不定式的區別比較大
如：I remember reading the book.我記得讀過這本書。（記得做過某事，已做）
I remember to read the book.我必須記得去讀這本書。（記住去做某事，未做）
The old lady forgot telling us the story and told us a second time.那個老太太忘記給我們講過這個故事，她又講了一遍。（忘記做過某事，此事已經發生）
I forgot to lock the door this morning.今天早晨我忘記鎖門了。（忘記去做某事，此事未做）
Though they were all tired, they wouldn't stop working.雖然他們都很累了，但是他們也不肯停止工作。（停止正在或經常做的事）
After walking a long time, he stopped to have a rest.走了好長時間之后，他停下來休息。（停止某件事，目的是去做另一件事）
Missing the train means waiting for another hour. 誤了這趟火車意味著再等一個小時。（意味著）
I mean to come early today.我打算今天早些來。（打算）
He regretted saying that to her face.他后悔當她面說那番話。（對做過的事情后悔）
I regret to tell you that I won't go with you.我很遺憾地告訴你，我不能和你一起去。（對要做的事遺憾）
Why not try knocking at the back door?為什么不試試敲后門。（試驗，試一試某種方法）
He will try to improve his spoken English.他要設法提高他的英語口語。（努力，企圖做某事）
They went on working after dark.天黑之后，他們繼續工作。（繼續原先沒有做完的事情）
After finishing the letter, he went on to read a book.寫完信后，他接著讀書。（繼而做另外一件事）
4）動名詞作介詞賓語
如：He is against dancing all night.他反對通宵跳舞。
注：下列短語中的to是介詞，不是不定式符號
如：in addition to除外， devote oneself to獻身于，look forward to期望， be used to習慣于， stick to堅持，lead to導致，object to反對，be opposed to反對，pay attention to注意等
如：He is used to working on the night shift.他已習慣上夜班。
We are so much looking forward to seeing you again.我們非常盼望再見到你。
4．做定語
如：The teacher has many reading materials.老師有很多閱讀材料。
Our teacher uses a very good teaching method.我們教師的教學方法很好。
注：動名詞和現在分詞作定語是有區別的。動名詞作定語，和它修飾的名詞在邏輯上沒有主謂關系，即它不是該名詞發出的動作，只是表明所修飾名詞的目的和用途。現在分詞作定語表示所修飾的詞與分詞有邏輯上的主謂關系。
如：a sleeping car= a car for sleeping臥車（動名詞）
a sleeping boy= a boy who is sleeping睡覺的男孩（分詞）
5．動名詞的復合結構
一般情況下，動名詞的邏輯主語為謂語動詞的主語。如果動名詞動作的發出者不是謂語動詞的主語，則需要有自己的邏輯主語。這種物主代詞或名詞所有格加動名詞就構成了動名詞的復合結構。
1） 邏輯主語是有生命的名詞，作主語時，必須名詞或代詞所有格，作賓語時（尤其在口語中），也可用名詞普通格或人稱代詞賓格。
如： Do you think my going there will be of any help? 你看我去會有什么幫助嗎？（作賓語）
The student's knowing English well helps him in learning French.這位學生通曉英語對他學法語很有幫助。（主語）
Do you mind my (me) smoking? 你介意我抽煙嗎？
2） 邏輯主語是無生命名詞時，一般只用名詞普通格。
如： Do you hear the rain pattering on the roof? 你聽見雨點打在屋頂上了嗎？
3）邏輯主語是指示代詞或不定代詞this, that, somebody, someone, nobody, anybody, anyone時，只用普通格。
如： She was woken up by somebody shouting outside. 她被外面喊叫的人吵醒了。
6．動名詞的時態
動名詞的一般式：動名詞的一般式表示動作與謂語動詞所表示的動作同時發生，或在謂語動詞表示的動作之后。
如：We are interested in collecting stamps.我們對集郵感興趣。
動名詞的完成式：動名詞的完成式所表示的動作發生在謂語動詞表示的動作之前。
如：We were praised for having finished the work ahead of time.我們因提前完成了這項工作而受到了表揚。
注：在介詞on, upon, for, after之后，常用一般式代替完成式，表示動作發生在謂語動作之前。
如：Excuse me for coming late.請原諒我來晚了。
第二部分 鞏固練習
用動詞適當形式填空：
1. The text needs___________ (explain) once again.
填 explaining/to be explained. need后面接動名詞作賓語主動表被動。
2. The movie is worth ___________ (see).
填seeing. be worth doing.表示值得做什么
3. I've had a hard time ________ (learn) English.
填 learning. have a hard time (in) doing sth.
4. I still remember __________ (take) you to Beijing for the first time.
填 taking. remember doing sth.表示記得做過某事。
5. Clint always remember __________ (turn) off the lights when he leaves the room.
填to return. remember to do記得去做某事
6. Now he regrets ________ ( not, go) to university.
填not going. regret doing sth. 對做過的事情后悔
7. We regret ________ (inform) you that the flight has been cancelled.
填 to inform. regret to do sth. 對要做的事遺憾
8. I regret _________ (let) slip that opportunity.
填letting. regret doing sth. 對做過的事情后悔
9. Peter went on ___________ (sleep) despite the noise.
填sleeping. go on doing繼續原先沒有做完的事情
10. He welcomed the new students and then went on __________ (explain) the college regulation.
填 to explain. go on to do sth. 繼而做另外一件事
11. Mr.Smith regretted _____ (blame) his secretary for the mistake, for he later discovered it was his own fault.
填 blaming. regret doing sth. 對做過的事情后悔
12. The boy is constantly being told not to scratch the paint off the wall, but he goes on ________ (do ) it all the time.
填doing. 繼續原先沒有做完的事情
13. You must tell me the truth. I insist on _______ (tell) the truth.
填telling. 介詞on后面用動名詞
搭配：
1. Seek answers to questions 尋找什么問題的答案（seek的過去式：sought）/動詞詞組
2. lay aside 擱置（lay的過去式：Laid）/動詞詞組
3. Be curious about 對什么好奇/形容詞詞組
4. Take apart （e.g. a watch） 拆散/動詞詞組
5. Combine sth. with sth. 把什么和什么結合在一起/動詞詞組
6. Carry out the experiment 完成試驗/動詞詞組
7. Belief in sth./sb. 相信某人或某事/名詞詞組
8. （there is）an explanation for sth. 解釋某事/名詞性詞組
9. There is a good reason why +句子 這就是為什么的原因
10. Not at all 一點也不/副此詞組
11. Regardless of 不管；無論/形容詞詞組
12. Succeed in sth./doing sth. 成工作某事/動詞詞組
13. The solutions to problems 問題的解決辦法/名詞的解決方法
14. In advance 提前/副詞詞組
15. Adapt sth. to sth. 使什么適應什么/動詞詞組
16. Make up one's mind 下定決心/動詞詞組
17. Once and for all 一勞永逸地/副詞詞組
18. Change in thinking 思想的轉變/名詞詞組
19. Make sth. necessary 事某事很必要/動詞詞組
20. In the light of sth. 根據，參照，考慮到/介詞詞組
21. Respect for sth. 對什么的尊敬/名詞詞組，動詞詞組
22. The difficulty comes up. 問題產生了
23. Base on sth. 根據什么/動詞詞組
24. It may take time for sth./sb. to do sth. 做某事花某人多長時間
25. Conditions for sth. 什么的條件/名詞詞組
語言點：
1. Belief的復數形式為beliefs
2. Well-known/著名的
3. Curious（adj.好奇的）——curiosity（n.好奇）；imagine（v.想象）-imagination（n.想象力）
4. Scientifically minded people 有科學頭腦的人
5. In cases where the explanation is unknown the scientific point of view is that there is a reason if it can only be discovered. 在對于現象還無法解釋的時候，科學的觀點是有理由相信遲早這種解釋是可以被發現的。
6. This means the ability to（做什么的能力） face the facts as they are（實事求是） regardless of what one has previously thought.
7. Agree（v.同意）-disagreeable（adj.令人討厭的）
8. The worker in science must face facts whether they are pleasant or unpleasant.
I didn't know whether to laugh or to cry when I heard the news.是…還是…
Whether he succeeds or fails， he has to do his best.
He doesn't know whether she is in Britain or she has gone to France.
9. Thomas Edison failed thousands of times before he succeeded in producing the first electric lamp.
10. Accept（v.接受）-acceptable（adj.可接受的）
11. Scientific truth offers an explanation that is acceptable only in the light of what is known at a particular time.
12. New ideas are frequently very slow to be accepted.
13. Continued progress 繼續的發展
14. 時態題：There is an experiment on the sprouting of seeds which has been running for more than 50 years.
Text B Solving Problems Scientifically
搭配：
1. Arouse one's curiosity 引起某人的注意/動詞詞組
2. Result from=arise from 由于/動詞詞組；result in 導致/動詞詞組
3. Give clue for doing sth. 為做某事提供線索/動詞詞組
4. Build a firm foundation for doing sth. 為做某事打下堅實的基礎/動詞詞組
5. Make an inference 做推論/動詞詞組
6. Turn out to be 結果是/動詞詞組
7. Check with 與什么相符/動詞詞組
語言點：
1. Once是連接詞，表示一旦。
2. A thoroughly understood problem is well started toward solution. Be well started toward 是什么的良好開端。
3. The development of industry has also brought about large numbers of problems which have to be solved.
4. Related questions 相關問題；unanswered questions 為回答的問題；controlled conditions 被控制的條件
5. Reliable（adj.可信賴的）-unreliable（adj.不可信賴的）
6. Should the observations or predictions turn out to be as expected， the scientist has added confidence in the probable truth of his hypothesis. = If the observations or predictions should turn out to be as expected， the scientist has added confidence in the probable truth of his hypothesis.
本課需要重點掌握的語法現象：動名詞
動名詞兼有動詞和名詞的特征。因此在句中可以做主語、表語、賓語和定語。
1．作主語
直接將動名詞放在句首作主語，謂語動詞用單數。
如：Seeing is believing. 百聞不如一見。
Swimming is the best exercise in summer.在夏天，游泳是最好的鍛煉方式。
注：a)動名詞和不定式都可以作主語，一般可以互換。但有時又略有區別。動名詞作主語往往表示一般或抽象的多次行為，不定式作主語表式具體的或一次性的動作。
如：Playing with fire is dangerous.（泛指玩火）
To play with fire will be dangerous.（指一具體動作）
b)在It is no use(good), not any use (good), useless 等后面一般用動名詞作主語。
如：It is no use arguing with him.同他爭論無用的。
It is no good learning English without practice.學英語不練是不行的。
2．作表語
如：The real problem is getting to know the difficulties of the students.現實的問題是了解學生的困難。
注：a)動名詞和不定式都可以做表語，區別在于：表示抽象的一般的行為時，多用動名詞；表示某次具體的動作或具有將來時的意義時，多用不定式。
如：My job is teaching English.我的工作是教英語。
My today's job is to teach you how to study English. 我今天的任務是教你如何學英語。
b) 動名詞作表語時不要與進行時態混淆。進行時態說明動作是由主語完成的。動名詞作表語，說明主語的性質和情況。
如：He is collecting stamps.他在集郵。（現在進行時）
His hobby is collecting stamps.他的愛好是集郵。（動名詞）
c) 動名詞和現在分詞作表語的區別：動名詞作表語說明主語的內容，而且可以轉換到句首作主語；現在分詞作表語，表示主語的特征，其作用相當于形容詞。
如：His favorite sport is running.他最喜愛的運動是跑步。
可以轉換為：Running is his favorite sport.
The film is very moving.這部影片很感人。
3．作賓語
1)必須接動名詞作賓語的動詞有：admit, appreciate, avoid, consider, delay, deny, finish, mind, postpone, risk等
如：We'd better postpone discussing it till next week.我們最好把這件事推遲到下星期討論。
2) 有些動詞既可以接動名詞也可以跟不定式作賓語。如：attempt, begin, continue, hate, like, love, start，need等。如果用動名詞，在意義上比較一般和抽象，時間觀念不強；如果用不定式則表示具體的動作，有將來時的含義。
如：The boys like playing football.這些男孩們喜歡踢足球。（經常性的動作）
Would you like to play football with us this Sunday? 這個周日愿意和我們一起踢球嗎？（指一次動作）
注：need, require, want作需要解時，后面須根動名詞或不定式的被動語態作賓語，這時動名詞的主動式表示被動的意義。
如：The window needs /wants/requires cleaning (to be cleaned).這個窗戶需要清洗。
3）在remember, forget, stop, mean, regret, try, go on等動詞后動名詞和不定式的區別比較大
如：I remember reading the book.我記得讀過這本書。（記得做過某事，已做）
I remember to read the book.我必須記得去讀這本書。（記住去做某事，未做）
The old lady forgot telling us the story and told us a second time.那個老太太忘記給我們講過這個故事，她又講了一遍。（忘記做過某事，此事已經發生）
I forgot to lock the door this morning.今天早晨我忘記鎖門了。（忘記去做某事，此事未做）
Though they were all tired, they wouldn't stop working.雖然他們都很累了，但是他們也不肯停止工作。（停止正在或經常做的事）
After walking a long time, he stopped to have a rest.走了好長時間之后，他停下來休息。（停止某件事，目的是去做另一件事）
Missing the train means waiting for another hour. 誤了這趟火車意味著再等一個小時。（意味著）
I mean to come early today.我打算今天早些來。（打算）
He regretted saying that to her face.他后悔當她面說那番話。（對做過的事情后悔）
I regret to tell you that I won't go with you.我很遺憾地告訴你，我不能和你一起去。（對要做的事遺憾）
Why not try knocking at the back door?為什么不試試敲后門。（試驗，試一試某種方法）
He will try to improve his spoken English.他要設法提高他的英語口語。（努力，企圖做某事）
They went on working after dark.天黑之后，他們繼續工作。（繼續原先沒有做完的事情）
After finishing the letter, he went on to read a book.寫完信后，他接著讀書。（繼而做另外一件事）
4）動名詞作介詞賓語
如：He is against dancing all night.他反對通宵跳舞。
注：下列短語中的to是介詞，不是不定式符號
如：in addition to除外， devote oneself to獻身于，look forward to期望， be used to習慣于， stick to堅持，lead to導致，object to反對，be opposed to反對，pay attention to注意等
如：He is used to working on the night shift.他已習慣上夜班。
We are so much looking forward to seeing you again.我們非常盼望再見到你。
4．做定語
如：The teacher has many reading materials.老師有很多閱讀材料。
Our teacher uses a very good teaching method.我們教師的教學方法很好。
注：動名詞和現在分詞作定語是有區別的。動名詞作定語，和它修飾的名詞在邏輯上沒有主謂關系，即它不是該名詞發出的動作，只是表明所修飾名詞的目的和用途。現在分詞作定語表示所修飾的詞與分詞有邏輯上的主謂關系。
如：a sleeping car= a car for sleeping臥車（動名詞）
a sleeping boy= a boy who is sleeping睡覺的男孩（分詞）
5．動名詞的復合結構
一般情況下，動名詞的邏輯主語為謂語動詞的主語。如果動名詞動作的發出者不是謂語動詞的主語，則需要有自己的邏輯主語。這種物主代詞或名詞所有格加動名詞就構成了動名詞的復合結構。
1） 邏輯主語是有生命的名詞，作主語時，必須名詞或代詞所有格，作賓語時（尤其在口語中），也可用名詞普通格或人稱代詞賓格。
如： Do you think my going there will be of any help? 你看我去會有什么幫助嗎？（作賓語）
The student's knowing English well helps him in learning French.這位學生通曉英語對他學法語很有幫助。（主語）
Do you mind my (me) smoking? 你介意我抽煙嗎？
2） 邏輯主語是無生命名詞時，一般只用名詞普通格。
如： Do you hear the rain pattering on the roof? 你聽見雨點打在屋頂上了嗎？
3）邏輯主語是指示代詞或不定代詞this, that, somebody, someone, nobody, anybody, anyone時，只用普通格。
如： She was woken up by somebody shouting outside. 她被外面喊叫的人吵醒了。
6．動名詞的時態
動名詞的一般式：動名詞的一般式表示動作與謂語動詞所表示的動作同時發生，或在謂語動詞表示的動作之后。
如：We are interested in collecting stamps.我們對集郵感興趣。
動名詞的完成式：動名詞的完成式所表示的動作發生在謂語動詞表示的動作之前。
如：We were praised for having finished the work ahead of time.我們因提前完成了這項工作而受到了表揚。
注：在介詞on, upon, for, after之后，常用一般式代替完成式，表示動作發生在謂語動作之前。
如：Excuse me for coming late.請原諒我來晚了。
第二部分 鞏固練習
用動詞適當形式填空：
1. The text needs___________ (explain) once again.
填 explaining/to be explained. need后面接動名詞作賓語主動表被動。
2. The movie is worth ___________ (see).
填seeing. be worth doing.表示值得做什么
3. I've had a hard time ________ (learn) English.
填 learning. have a hard time (in) doing sth.
4. I still remember __________ (take) you to Beijing for the first time.
填 taking. remember doing sth.表示記得做過某事。
5. Clint always remember __________ (turn) off the lights when he leaves the room.
填to return. remember to do記得去做某事
6. Now he regrets ________ ( not, go) to university.
填not going. regret doing sth. 對做過的事情后悔
7. We regret ________ (inform) you that the flight has been cancelled.
填 to inform. regret to do sth. 對要做的事遺憾
8. I regret _________ (let) slip that opportunity.
填letting. regret doing sth. 對做過的事情后悔
9. Peter went on ___________ (sleep) despite the noise.
填sleeping. go on doing繼續原先沒有做完的事情
10. He welcomed the new students and then went on __________ (explain) the college regulation.
填 to explain. go on to do sth. 繼而做另外一件事
11. Mr.Smith regretted _____ (blame) his secretary for the mistake, for he later discovered it was his own fault.
填 blaming. regret doing sth. 對做過的事情后悔
12. The boy is constantly being told not to scratch the paint off the wall, but he goes on ________ (do ) it all the time.
填doing. 繼續原先沒有做完的事情
13. You must tell me the truth. I insist on _______ (tell) the truth.
填telling. 介詞on后面用動名詞