参考答案及解析：

巩固与拓展

1. His success result from part in his ability to sell the product and
in part from his policy of expanding during periods of economical __________
decline, when most of his competitors were reducing their investments.

economical -> economic
economical意为“节俭的”，economic意为“经济的”，此处说的是经济滑坡，所以应该是economic decline。

2. There is a train which leaves London at 5pm and
arrives Cambridge at 6:45pm. __________

arrives -> reach或arrives后加in
arrive是不及物动词，表示“到达”时如果后面要跟地方就要加上介词或者将其改成与其同义的及物动词reach。

3. In fact, psychologists adapt a similar approach to scientists in other fields ______

adapt -> adopt
adapt意为“使…适应”，adopt意为“采用，收养”，根据句意应该是用后者。

4. They are far more probable to report that they don’t have the time to ______
read the papers and have no interest in the content.

probable -> likely
两者都有“可能的’之意，但是用probable时，主语只能是物或者形式主语it，而使用likely对于主语没有特别的要求。

5. Ever since the enclosures, wool and then woolen cloth
had been the principle exports of England ________

principle -> principal
principle意为“原则”；principal可以作形容词，意为“主要的”，也可作名词，意为“校长”。此处意为“主要出口商品”，故应该使用principal。

综合训练：

1. and -> but
根据上下文，此处应为转折关系

2. other -> others
这里是some….others的固定用法。

3. for -> since
for和since都可以表示“因为”，但是for表示原因引导得从句一般放在句末，所以在此处不对

4. made -> made it
句子主语是law，位于是made，easier是宾语补足语，逻辑宾语是easier后面的to get a divorce，可见此句缺少形式宾语it。

5. end -> ends
主语one marriage in every three 是单数，故谓语动词也要用单数。

6. with -> of
形容词tolerant后面只能用of。还原原句为Society is now more tolerant than it used to be ( tolerant) of unmarried people。

7. the fact -> the fact that
fact之后的部分是同位语从句，补充说明fact

8. cause -> result
s a cause of意为“作为…的原因”，as a result of意为“作为…的结果”，根据上下文语义，应该用后者。

9. consist -> consisting或consist前加which或that
句子结构混乱。简单句中不能同时出现两个谓语动词。

10.are -> were