review of units 1—3
一. 重点词汇
1. as
as作为连词,引导时间状语从句,“当……的时候”,一般用于一般过去时。
例如:
as he explored the sea,he took a lot of pictures. 他在探海时,拍了许多照片。
还可以引导原因状语从句,只说明一般的因果关系,语气比because弱,说明比较明显的原因,它引导的从句通常放在句首,有时也放在句尾。
例如:
as the car is expensive,we can’t buy it. 由于汽车太贵,我们买不起。
as everybody has come,we can set off. 既然大家都到了,我们可以动身了。
as soon as 一……就
例如:
as soon as he arrived in france,he called me. 他一到法国,就给我打电话。
as…as… 表示双方程度相等,“和……一样”。
基本句式:
a、主语+谓语(系动词)+as+原级形容词+as…
例如:
xiao li is as tall as his brother. 小李和他哥哥一样高。
your jacket is as new as mine. 你的茄克衫和我的一样新。
b、主语+谓语(行为动词)+as+ 原级副词 +as…
例如:
he speaks french as fluently as you. 他说法语和你说得一样流利。
wang ying teaches maths as conscientiously as her sister.王莹教数学和她姐姐一