People           about what our future will look like for thousands of years.

have been wondering

wonder

wondered

will wonder

考查动词时态。句意：数千年以来人们一直想知道我们未来是什么样子。根据时间状语 for thousands of years可知，描述从过去开始一直持续到现在的动作，用现在完成进行时。故选A项。

Every evening after dinner, if not ________ from work, I will spend some time walking my dog.

being tired

tiring

tired

to be tired

考查省略句。当状语从句的主语和主句主语一致，且状语从句中有be动词的时候，可以把状语从句的主语和be动词一起省略，本题if后面省略了I am，句意：每天晚上吃完晚饭以后，如果不是很累，我就会花点时间来遛狗。故C正确。

"Society" is a(n)              term;it may mean much or nothing.

autonomous

ambiguous

fragrant

fragile

考查形容词词义辨析。句意：“社会”是一个模棱两可的词；它可能意味着很多，也可能没有意义。autonmous 自治的；ambiguous模棱两可的；fragrant芳香的；fragile脆弱的。结合后文it may mean much or nothing可知，空格处填ambiguous模棱两可的。故选B项。

---I'm sorry,but it's my seat.

---           I didn't know it's yours.

What if

I beg your pardon

That's all right

What for

考查交际用语。句意：---对不起，这是我的座位。---请原谅。我不知道这是你的。A. What if如果.....将会怎么样；B. I beg your pardon. 对不起，请原谅；C.That's all right没关系；D. What for为什么。根据"Idon't know it's yours."可知坐了别人的座位，请求别人原谅。故选B项。

Small sailboats can easily turn over in the water ________.

if not managed carefully

if are not managed carefully

unless not managed carefully

unless are not managed carefully