高一必修二：Unit 3 reading 知識(shí)點(diǎn)講解
unit 3 computer知識(shí)點(diǎn)講解
原創(chuàng)人：北大附中河南分校 王萍
1. i began as a calculating machine in france in1642.
translate：__________________________________________________
現(xiàn)在分詞作定語(yǔ)可以表示修飾詞的性質(zhì)，特征。現(xiàn)在分詞通常表示主動(dòng)意思
translate: excitingnews________ arunning man__________
thetrain leaving at ten_______ ___
fallingleaves_______ fallenleaves_________
a surprising look____________ asurprised look___________
連接高考：
1 the _____ look on her face suggested that she______ itbefore.
a surprising; wouldn’tknow b suprising; hadn’t know
c surprising; hadn’tknow d surprised; shouldn’t know
2 a communicative satellite______ as much as 3.5 tons was sentup into space last week.
awighing b weighed cto beweighed d being weighed
3 scientists have______ that the world’s population will doubleby the end of this century.
a numbered bincluded ccalculated d designed
2. i developed very slowly and it took nearly two hundred yearsbefore i was built as an analytical machine by charlesbabbage.
before用于這類句型的結(jié)構(gòu)有：
it didn’t take/was long before------過(guò)了不久就-----
it will take/ be longbefore------要過(guò)很久----
it won’t take/be long before------不久-----
translate：
it didn’t take long before the fire was under control
it will be five years before we meet again
選學(xué)：
① this / it is the first / second…time +that 從句。that從句一般用現(xiàn)在完成時(shí)，如果把前邊的is改為was，則that從句用過(guò)去完成時(shí)。如：
this is the first time i have come here.
it was the third time (that) he had made the same mistake.
② it is / has been +一段時(shí)間 + since從句。since從句中用過(guò)去完成時(shí)。
it was ten years since we had had such a wonderful time.
③ be about todo…when…意為“即將……（這時(shí)）突然……”。如：
i was about to go out when the telephone rang.
④ be (was /were) + doing… when…意為“正在干……（這時(shí)）突然……”。
they were reading when tom shouted in pain.
⑤ hardly had…done…when… ; no soonerhad…done…than…
when 和than從句里用一般過(guò)去時(shí)，表示“剛剛……就……”。如：
hardly (no sooner) had i got home when (than) the rain poureddown.