有非常详尽的讲解,是笔者多年一点一点的积累。
The fish will go bad __________ you __________ put it in the fridge.
答案：if, don’t
解析：考查条件复合句。要熟悉“保持句意”的改写，如简单句和复合句的转换，两句并一句，形容词，副词比较等句型，不用句型的转换，词语的不同搭配。请看下面的例句和分析：
1). It was eleven o’clock when he finished his homework last night.
He finish his homework it was eleven o’clock.
本句是改为not until 句型，用didn’t, until.
2). He is the tallest in his class.
No one in his class is as as he.
本句是最高级句型改为原等级句型，用else, tall.
3). He didn’t make as many mistakes in his homework as you.
He mistakes in his homework 本句是 as(so)…as 句型改为用带than的句型，用made fewer…than. mistakes 是可数名词，别误用修饰不可数名词的less。
4). These stamps belong to my elder brother.
These stamps are elder 原句中的belong to 改为are ，动词转换，用法不同，应用brother’s.
5). The box is so heavy that I can’t carry it.
The box isn’t for me to carry.
本句是复合句改为简单句，且否定结构的位置有变化，需要用heavy的反义词，故用light enough,误用成too…to结构。
6). The question is very difficult. No one can answer it.
The question is answer.
本句为两句合并成一句，原句有否定意义，应用too…for anyone to,别误用成so that anybody can. 如answer后it,才可用so…that结构，因too…to结构句子是简单句，而so...that是复合句。英语中考改写句子题目中，一般每句填写两个词，很少有上面一些例句中填写一个或三个词的题目。
7). She was so weak that she couldn’t take care of her baby.
She was _________ weak _________ take care of her baby.
本句为too…to结构。原句意思是：她身体太弱，不能照顾孩子。too…to … 句型表示“太……