13. All that can be done ___. a. has done b. has been done c. have done d. have been done 14. One or perhaps more pages ___. a. is missing b. has been missed c. are missing d. was missing 15. More than one worker ___ dismissed. a. have been ...
s not surprising even normal parental anxiety can be amplified. And many middle-class parents have gotten used to managing their children’s time and shuttling them to various enriching activities, so the idea of letting them out on their own can s...
2) 情态动词 除ought 和have 外,后面只能接不带to 的不定式。 3) 情态动词没有人称,数的变化,即情态动词第三人称单数不加-s。 4) 情态动词没有非谓语形式,即没有不定式,分词,等形式。 比较can 和be able to 1)can could 表示能力;可能(过去时用could), 只用于现在式和...
if had done XX would have done XX 要是...就... 例句: If I had met you two years ago I would've become a slim person. 我要是两年前就遇到你,我现在就是个瘦人了。 make (the) bi...
2.带情态动词的被动语态:must (can, may, should, need, would) be done 3. 一般过去时: was (were) done * 4. 一般将来时: will (shall) be done * 5. 现在进行时: am (is, are) being done 6. 现在完成时: have (has) been done ...
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