1、The headmaster let me do the work again（反意疑问句）

The headmaster let me do the work again ,didn't he?
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此句是过去时，为什么DO不用过去式呢？

2、The maths problem is too difficult for him to work out(改为复合句）

The maths problem is so hard that he can't work out
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为什么不用difficult，用HARD呢？

求正确答案、正确答案的解答与题目要点。
3、Football is the most popular sport in western countries

Football is __________than___________in western countries
（要点:最高级的句型转换more than any other+单数名词）

4、There isn't anything wrong with my watch.
______________________________with my watch.

5、My pen friends often write to me.
I often _______my pen friends.

6、I don't know what I should say at the meeting.
I don't know what _________________at the meeting.

7、Tom finished his homework just now.
Tom's homework ________________just now.

8、I couldn't pass the English exam if you didn't help me
I couldn't pass the English exam __________
(if+not转换＝？）

7、怎样把句子转换成宾语从句？（请举例子，并列出一条规律）

1.情态动词（can、may、must等）和使役动词（make、let、get)后面接动词原型，这里是让...做...，只能用let+do(动词原型）。相当于to do里面的do肯定就是用动词原型一样。
2.这个估计是你看错了，因为hard=difficult，两个词可以随便用。
3.more popular... any other sports
最高级可以换成比较级+than any other 的形式。如：He is taller than any other boys in the class= He is the tallest boy in the class.他是班上最高的男生。这里要注意，一定要有other把他自己排除在外。不能说 He is taller than any boys in his class.
4.Everything is ok... 把双重否定isn't..wrong换成肯定。
5.hear from. 笔友经常给我写信，也就我经常收到笔友的信，用hear from. 注意hear from就是“收到..的信”，后面不能再接“信”。
6.to say。宾语短语换成不定式。这种形式很常见。如：I want to learn how can I control the machine=I want to learn how to control the machine.我想学习怎样操纵这个机器。类似的有what to, how to, when to等等。
7.was finished. 这题就是简单的主动语态换成被动语态。要注意的地方就是人称数量的变化，时态的一致等。
8.without your help.这种题目比较特殊，所以不能用某个特定的词或短语代替if..not。如：You couldn't hear the knocking on the door,if you are not awake. 如果你睡着了，你就听不到敲门声。这句就不能用without的短语代替if..not。所以除了“缺少,没有...”的意思用“without”外，其他的要看情形而定。

最后一问不明确。其实建立宾语从句就是用整个句子担当宾语的成分。如：I know that he is a hard-work student.我知道他是个刻苦的学生。（“他是个刻苦的学生”整个句子担当know的宾语。）He has realized that he could do nothing but wait.他意识到除了等待，别无他途。所以，你先加强宾语从句的辨别能力，之后再把要求的句子转化成宾语从句就比较简单了。
大家有好的意见吗？请告知，谢谢。