This is the only answer ______ right.

[　　]

A．which we think is

B．what we think it is

C．that we think is

D．what we think seems

The river ______ are covered with trees is very long.

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Last week, only two people came to look at the house, ______ wanted to buy it.

[　　]

Let's meet at the same place ______ yesterday.

[　　]

When considering how to settle the problem, the most important factor was weather, which he had ______.

[　　]

Those successful deaf dancers think that dancing is an activity ______ sight matters more than hearing.

[　　]

I shall not believe it until I see it ________ myself.

[　　]

The visiting Minister expressed his satisfaction with his talks, ______ that he had enjoyed his stay here.

[　　]

The computer center ______ last year, is very popular among the students in this school.

[　　]

Although the town had been attacked by the storm several times, ______ was done.

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