八级下册语法专题一情态动词should与could

情态动词should与could的用法

●语法讲解

1．should是情态动词shall的过去式，但有时并不表示过去。 (1)表示委婉的劝告或建议，意为“应该”。如： Youshouldhandinyourcompositionatonce. 你应该立刻交上你的作文。

(2)表示可能性或推断，意为“可能；应该”。如： Ithinktheyshouldbetherenow. 我想他们现在应该在那里。

(3)用于特殊疑问句中，表示意外、惊奇、不能理解等强烈感情。如： Howshouldyouknowthat? 你是怎么知道那件事的？ Whatshouldyoudotorelax? 你该做什么来放松呢？

2．could是情态动词can的过去式，但有时并不表示过去。 (1)表示提议，比can更客气、委婉。 Icoulddotheshoppingforyou,ifyouaretired. 如果你累了，我能帮你买东西。

(2)表示请求，语气比can更客气、委婉。 Couldyoushowmethewaytothehospital? 你能告诉我去医院的路吗？ ●语法精练 Ⅰ.单项选择

()1.Schools________allowstudentsatleastonehour adayforsports.

A．would B．might C．shouldD．could

()2.________youtellmehowtogettothepost office?

A．MustB．Need C．CouldD．Should

()3.—WhencanIcomeforthephotos?Ineedthem tomorrowafternoon.

—They________bereadyby12：00. A．canB．should C．mightD．need

()4.—CouldIborrowyourdictionary? —Ofcourseyou________． A．canB．must C．shouldD．will

()5.Thebasketball________his.Helovesplaying basketball.

A．maybeB．maybe

C．mayisD．maynot

()6.We________keepthenewtrafficlawandlearnhow toprotectourselves. A．willB．would C．shallD．should

()7.—Couldyoupleasehelpmedomyhomework? —Sorry.I________．You________doitbyyourself. A．could;may

B．couldn't;should C．can't;should D．can't;may

()8.—Howwastheyouthclublastnight,Mark? —Itwasgreatfun.You________come. A．mustB．can C．shouldD．may

Ⅱ.根据句意用should或could填空

1．Sally________makedumplingsbyherselfwhenshewas onlyfiveyearsold.

2．Inschool,alltheclassmates__________getonwell witheachother.

3．You________callherifyouhavesomethingimportant totellher.

4．You_________notdriveafterdrinking.

5．_________Iuseyourmobilephone，please?