四、事實羅列詞匯：在這些詞匯后就是關(guān)鍵和重要的事實性息，actually, in fact, as a matter of fact,etc。

　　五、序數(shù)詞后面，最重要的是the first, firstly and finally。

　　六、情態(tài)動詞：sb.has got to, can , could, may, might, need,should, ought to,etc。

　　七、重要形容詞：表示重要的詞，important, crucial, chief,major,significant, the only, unique, essential, necessary, vital, etc。