请教语法题

jackylpt

1. Generally, systems fo vocal communications are recognized as different languages if they can not be understood without specific learning by both parties, though the ___ .
A  precise limits of mutual intelligibility, which are hard to draw.
B  precise limits of mutual intelligibility are hard to draw.
答案是B, 但好象though 后不能接句子,只能是短语, even though才行呀,why???

2.After ( their )  birth in the spring,  young woodchucks (may ) stay with their mother ( for ) two months or ( more) than.
答案是D, 怎改??

3.Charltown PEI.___ the character Ann, in the famous Canadian novel Ann of Green Gables, grows up.
A where      B is where
答案是B , 但我选A , 因为动词是grows up, 所以不能有两动词呀,?????

4. Ralph Nadar,(  in early 1970s) , help set standards, ( with which ) automobile companies have ( ever since)  had to ( comply)
The answer is A , 怎改呀?/ 我认为C 也不对呀

谢谢指导

lucyyyh

1. though是conj. 所以可以接句子. A是不正确的,因为缺少谓语.B是一个由 though引导的让步状语从句.
though:  "虽然"    even though: "即使"   意思不一样.这道题选B.

3.这里是一个表语从句.主语是Charltown PEI, 主句谓语是is, 后面有一个表语从句where the character Ann grows up, grow up是表语从句的谓语.

lucyyyh

4. in early 1970s-----> in the early 1970s.