人教八年级英语下册 Unit 6 条件状语从句语法详解及强化练习

Unit 6 条件状语从句语法详解及练习

一、unless引导的条件状语从句

unles用作连词，意为“除非；如果不”，引导条件状语从句，若主句为一-般将来时、祈使句或谓语中含有情态动词时，从句常用一-般现在时表示将来。Nobody will come to the party unless you change the date.

如果你不改变日期，没有人会参加聚会。

Don't go out unless your mother allows you.

除非你妈妈允许，否则你不要出去。

You can't pass the exam unless you study harder.

你如果不更加努力学习，就不能通过考试。

unless通常可与if...not结构进行转换。

I'll go there unless it rains. =I'll go there if it doesn‘ t rain.

如果不下雨，我就去那儿。

（2018·吉林）

中考链接

I sleep with the window open _____ it's really cold.

A unless

B till

C or

解析：我们可用“句意分析法”解答本题。

unless意为“除非，如果不“；till意为“直到为止”；or意为“或者，否则”。联系空格

前“我开着窗户睡觉”和空格后“天确实冷”并结合选项可知，句意为“除非天确实

冷，我都是开着窗户睡觉”。故选A

二、as soon as引导的时间状语从句

as soon as意为" 一...就... ''，引导时间状语从句。若主句为一般将来时，从句常用一般现时

表示将来。

I will call you up as soon as I return home.

我一回到家就给你打电话。

The boy got up as soon as the alarm clock went off.

闹钟一响，那个男孩就起床了。

2017重庆A卷

中考链接

As soon as the rain _____ , they will go out to pick apples

A stops.

B stopped

C will stop

D. is stopping

解析：我们可用“语法分析法”解答本题。as soon as意为"一...... 就...... ''，引导时间状语

从句。在含有 as soon as引导的时间状语从句的主从复合句中，当主句用一般将来时时，从句用一般现在时表示将来，故选A。

句意：雨一停，他们就出去摘苹果。答案：A

三、so...that...结构

so...that...意为“如此……以至于……”，that引导结果状语从句，其句型为：主语+谓语+so+容词/副词+that从句。在此句型中，so后面用形容词还是副词，取决于主句的谓语动词是连系动词还是实义动词。

I was so nervous that I couldn't fall asleep.

我如此紧张以至于睡不着。

She worked so hard that she passed the exam.

她学习很努力，因此通过了这次考试。

当that引导的结果状语从句是肯定句时,so...th at...可以与be...e nough to 进行转换。

换：当that引导的结果状语从句是否定句时，可与too...t o...或be not...enough to do进行转换。

The boy is so clever that he can answer the question easily. =The boy is clever enough to answer the question easily.这个男孩如此聪以至于他可以很容易地回答这个问题。

The girl is s o young that she can't look a fter herself. =The girl is too young to look after herself. =The girl isn't old enough to look after h erself.

这个女孩这么小，以至于不能照顾自己。

[拓展]“如此......以至于......''的其他常见表法方式：

①so+形容词+a/an+单数可数名词+that从句=

such+a/an+形容词+单数可数名词+that从句。

It was so fine a day yesterday that we all went out for a picnic. = It was such a fine day yesterday tha t we all went out for a picnic.

昨天天气很好，我们都出去野餐了。

②such+形容词+复数可数名词/不可数名词+

that从句。

They are such good students that the teacher likes them.

他们都是很好的学生，老师喜欢他们。

It was such fine weather yesterday that we went swimming.

昨天天气很好，我们去游泳了。

③so+many/much/few/little (少)+名词+that 从句。

There was so much work to do that everybody got bored.

有这么多工作要做，人人都感到厌烦了。