need(需要)
的用法與dare幾乎完全相同。即在否定句或疑問句中，和其他情態(tài)動詞一樣，本身無變化，后面用不帶to的動詞不定式；在肯定句中時，和實義動詞一樣，后面的動詞不定式要帶to，第三人稱單數(shù)現(xiàn)在一般時加-s，并有時態(tài)的變化。如：
Need we return the magazines today?我們今天需要把雜志還回去嗎?
Every member needs to pay only a little money a year to get medical care.每個成員每年只需繳一點錢就可以得到醫(yī)療。
You need not write down your translation. You may do it orally. 你們不必寫下這個翻譯練習，口頭做就行了。
[注]與dare一樣，在否定句或疑問句里，need也可和實義動詞相同，用助動詞to do來幫助，后面的動詞不定式必須帶to。如：
Do they need to take any tools with them? －No., they don't need to.他們需要帶工具嗎? --不需要。
He did not need to go there early that day. 那天他不必早去。
need后面有名詞作賓語時
完全用作實義動詞，表示"需要"或"缺乏"某件事物。這時，它的變化和一般實義動詞完全相同。如：
I need a dictionary.我需要字典。
You need a hair-cut. 你該理發(fā)了。
Do you need a fountain-pen? 你需要一支自來水筆嗎?
I don't need a new jacket. 我不需要一件新茄克衫。
Mary looks tried，she needs a rest. 瑪麗看上去累了，需要休息。
Needn't后加動詞不定式(不帶to)的完成式時
指過去已做了但勿須做的動作。如：
You needn't have watered the vegetables，as it is going to rain.你滿可以不必澆菜，天要下雨了。
You needn't have brought your umbrella. We are going by taxi你滿可以不必帶傘，我們要坐出租汽車去。
[注一]注意didn't have to和didn't nee to則常表示過去未做也勿須做的動作。如：
I didn't have to interpret it for her，for she knows Chinese.我勿須為她翻譯，她懂漢語。
I didn't need to take a taxi； it is only five minutes walk to the station.到車站只須走五分鐘，我不需要坐出租汽車。
[注二] used to和had better也可看作是情態(tài)動詞。情態(tài)動詞used to表示過去的習慣，但現(xiàn)在已無此習慣(would表過去習慣時則無此含義)。如：
When I was young，I used to play football.我小時常踢足球。
He didn't use to come. (或用usedn't to)他過去不常來。
Did he used to come? (亦可說used he to...?)他過去常來嗎?had better表可取，意為"應(yīng)該"或"最好"。如：
We had better go now. 我們最好走吧。
You'd better stop now.你現(xiàn)在應(yīng)該停下來。(對長輩不可用had better)
Hadn't we better go now? 我們現(xiàn)在走不好嗎?(had better一般不用于肯定疑問句)