高中英语 语法精讲（Unit 13The water planet）人教版
<p> 语法精讲 情态动词</p><p> 情态动词是动词的一种，顾名思义，表示说话人的情感或态度，认为“可能/应当/必要”，或表达“怀疑/命令/许可”等。情态动词没有人称和数的变化。情态动词本身词义不全，不能单独作谓语，必须和动词原形连用，共同构成谓语动词。有些情态动词有过去式，有些则没有。</p><p> 如：<span word="can">can</span>-<span word="could">could</span>,<span word="may">may</span>-<span word="might">might</span>,<span word="shall">shall</span>-<span word="should">should</span>,<span word="will">will</span>-<span word="would">would</span>,<span word="have">have</span> <span word="to">to</span> -<span word="had">had</span> <span word="to">to</span>,<span word="dare">dare</span>-<span word="dared">dared</span>;但<span word="must">must</span>,<span word="ought">ought</span> <span word="to">to</span> ,<span word="had">had</span> <span word="better">better</span>则只有一种形式。</p><p> 1. <span word="can">can</span>和<span word="could">could</span></p><p> ①表示“现在的能力”用<span word="can">can</span>，“过去的能力”用<span word="could">could</span>。</p><p> <span word="We">We</span> <span word="can">can</span> <span word="use">use</span> <span word="the">the</span> <span word="computer">computer</span> <span word="now">now</span>,<span word="but">but</span> <span word="we">we</span> <span word="couldn">couldn</span>’<span word="t">t</span> 10 <span word="years">years</span> <span word="ago">ago</span>.</p><p> ②表示“许可”或征询对方的许可，可用<span word="can">can</span>,<span word="could">could</span>（语气委婉，不表示过去），用<span word="may">may</span>（较正式），回答时不用<span word="could">could</span>.</p><p> —<span word="Can">Can</span>/<span word="Could">Could</span>/<span word="May">May</span> <span word="I">I</span> <span word="go">go</span> <span word="now">now</span>?</p><p> —<span word="Yes">Yes</span>,<span word="you">you</span> <span word="can">can</span>/<span word="may">may</span>.</p><p> ③表示“可能性”时，<span word="can">can</span>多用于否定句和疑问句，表“不可能，可能吗”之意。</p><p> 肯定句可用<span word="could">could</span>,<span word="may">may</span>,<span word="might">might</span>（语气更不地道）</p><p> <span word="The">The</span> <span word="story">story</span> <span word="could">could</span>/<span word="may">may</span> /<span word="might">might</span>/<span word="be">be</span> <span word="true">true</span>.</p><p> <span word="He">He</span> <span word="can">can</span>’<span word="t">t</span> <span word="be">be</span> <span word="at">at</span> <span word="home">home</span> <span word="now">now</span>.</p><p> ④<span word="can">can</span>和<span word="be">be</span> <span word="able">able</span> <span word="to">to</span> 都可以表示能力，但<span word="can">can</span>/<span word="could">could</span>表一般性的程度上的能力。</p><p> <span word="be">be</span> <span word="able">able</span> <span word="to">to</span>则表示具体的成功的做成某事。</p>
页:
[1]