江西成人高考高起点英语语法归纳与练习十四(2)

来源:
江西成考网
发布日期
2017年04月19日

摘要:    lesson 14  情态动词(一)     内 容 提 要     情态动词有can(能),may(可以),must(必须),have to(不得不),ought to(应该),dare(敢),used to(过去经常),had better(最好),would rather(宁愿)。在肯定句中它们后边都要接 动词原形 .在否定句中,can,may,must和dare后边加not;have to和o

me now.你还是现在回家为好。

    3. must表示“必须”或“应当”、“一定”

    3) The formation of snow must be occurring [A] slowly [B] , in calm air, and at a temperature near [C] the freezing point [D] .

    4. have to 加动词原形,表示“不得不”,“必须”,它比must更强调客观

    Tom had to work into the deep night everyday to earn a living. 汤姆为了生计每天都得工作到深夜。

    5. should 表示“劝告”,“建议”或“义务”时,译作“应当”,或表示“预测”和“可能”

    He should take care of his parents as they are old enough not to live on themselves. 由于父母亲老了,不能自理,他应当照顾他们。

    He should be there now. 他可能到了。

    should have done在虚拟语气中表示“责备或后悔”

    6. ought ,只有一种形式,即ought后必须加to,然后跟接动词原形表示“有义务”或“必要”做某事,译为“应当,应该”

    4) The traditional goal of science is to discover how things are,not how they ought .

    [A] to[B] to be[C] be[D] have been

    5) You are quite right;I am inferring in my comments [A] that McGraw had not ought to [B] have broken [C] in the room without his permission [D] .

    7. dare 可以用作情态动词,后面跟不带to的动词不定式,这主要用于否定句中,它本身可有现在时第三人称单数,词尾加s,它还可以有ING分词形式(daring)和过去式及ED分词形式(dared)

    6) Although Oriental ideas of woman's sub