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2019年6月大學(xué)英語(yǔ)四級(jí)重點(diǎn)語(yǔ)法知識(shí)盤點(diǎn)
英語(yǔ)四級(jí)重點(diǎn)語(yǔ)法知識(shí)：比較狀語(yǔ)從句
than，as…as…，not so as…，(not) the same as，the+比較級(jí);
eg：Light travels fast than sound.
the+比較級(jí)：
eg：The sooner，the better.
(1)當(dāng)……的時(shí)候：while，when，as ;
when：強(qiáng)調(diào)一件事情正在發(fā)生的時(shí)候，另外一件事情突然發(fā)生;
eg：When I was watching TV, my mother came back.
while：強(qiáng)調(diào)兩個(gè)動(dòng)作同時(shí)進(jìn)行，一邊……一邊……;
eg：My father is cooking while my mother is reading newspaper.
as："隨時(shí)間推移"
eg：As time went by, the days became longer and longer.
(2)一……就……：as soon as，主將從現(xiàn);用directly，immediately， instantly連接兩個(gè)句子;一些名詞如the minute，the moment，the instant也可表示;no sooner… than，hardly… when后面的句子需要倒裝;
eg：I will write to you the moment/minute I arrived in Paris.
(3)特殊單詞：by the time that，every/each time(使用時(shí)后面不要再加when)
(4)till&until：
① 肯定形式表示的意思是"做某事直至某時(shí)"，動(dòng)詞必須是延續(xù)性的;
否定形式表達(dá)的意思是"直至某時(shí)才做某事"，一般用until，動(dòng)詞為延續(xù)性或非延續(xù)性都可以;
eg: I slept until midnight.
Wait till I call you.
She didn't arrive until 6 o'clock.
② Until可用于句首，而till通常不用于句首，通常用于句中;
eg: Until you told me, I had heard nothing of what happened.
eg：As you sleep you pass through a sequence of sleep states—light sleep, deep sleep and REM (rapid eye movement) sleep—that repeats approximately every 90 minutes.