赌博游戏导航网址_赌博网址大全-澳门真人在线赌博网站大全

当前位置:主页 > 考试 > 学历类 > 高考 > 各科备考 > 高考英语备考 > >

高考英语语法:情态动词详解

来源::未知 | 作者:admin | 本文已影响
  1、情态动词 + have done sth
  这个结构有着特殊意义:用来表示猜测(设想可能发生过什么事情)或
  想象(设想可能出现过什么不同的情况)
  ①should (ought to) have done sth 本来该做而未做
  This wall oughtn’t to have been painted blue.
  ②need have done sth 本来有必要做而未做
  You needn’t have told her the news.
  ③must have done sth 对过去所做动作的肯定推测
  ---We went to Paris.
  ---That must have been nice.
  ④can have done sth 对过去所做动作的否定或疑问推测
  I don’t think he can have heard you. Call again.
  Where can John have put the matches?
  ⑤may (might) have done sth 过去可能发生某事,与could相比,may和 might可能性较小,might 可能性更小;might 也可表示过去可能发生而未发生的事情。
  Polly’s very late----she may (might) have missed her etrain.
  You were stupid to try climbing there. You might have killed youself
  ⑥could have done sth
  ●推测过去”可能“发生某事 (同can, 但can不用肯定句)
  She could have gone off with some friends.
  ●表示过去没有实现的可能性:某事可能发生,但却没有发生
  You were stupid to go skiing there----you could have broken your leg.
  ●表示有能力做而未做(虚拟语气)
  You could have helped me !
  (You were able to help me, but you didn’t.)
  2、can could be able to 表示”能力“
  ●can 通常表示现在的或”一般的能力“---即你无论什么时候想做就能
  做到的能力, 指单纯的表示一个人有某种能力。
  You can certainly cook, even if you can’t do anything else.
  ●be able to表示某人通过努力、克服困难做成某事。
  will be able to 表示将来的能力
  I’ll be able to speak German in another few months.
  ●could 表达 ”一般的能力“---即你过去想干什么就可以干什么
  She could sing like an angel when she was a kid.
  但could 不能表达过去某种具体的能力,此时用was able to, managed to 或 succeeded in 等
  How many eggs were you able to get ?
  3、can, could, may和might 表示”可能性“
  ●可用来表示:①理论上的可能性(不涉及是否真发生);②提出建议
  (提出解决某个问题的可能办法或者采取的行动);③在问句或否定句中表达现在的可能性)
  Anybody who wants to can become a prison visitor.
  ①---What shall we do ?
  ---We can try asking Lucy for help. ②
  Who can that be at the door ? Can it be Polly?    ③
  ●may 可用来表达:①将来的可能性;②说话时某事可能是真实的
  We may go climbing this summer.   ①
  You may be right.          ②
  ●could / might 可用来表示: ①说话时某事可能是真实的;②将来
  某事有可能发生,但不表示特别可能发生。
  You could be right, but I don’t think you are.  ①
  It could rain later on this evening.     ②
  4、can, could, may 和might表示“允许”
  ①请求允许:它们都可以表示请求允许做某事,could 和 might并不是表示过去
  Can (May, Could) I borrow your umbrella ?
  ②允许:当我们允许某人做某事时,我们用can和may来表达,而不能使用could和might
  You may / can watch TV for as long as you like. (不用could, might; mustn’t 有“拒绝”的意思)
  ---Could I use your phone?
  ---Yes, of course you can /may. (No, you can’t / may not.)

分享到: 更多
赌博游戏导航网址_赌博网址大全-澳门真人在线赌博网站大全

随机阅读TODAY'S FOCUS