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0, 1960 is the year when the revolution took place.

1960 is the year in which the revolution took place.

It is in 1960 that the revolution took place.

1, July is the month when the weather is usually the hottest.

July is the month in which the weather is usually the hottest.

It is in July that the weather is usually the hottest.

2, You’d better tell me the reason why he didn’t turn up.

You’d better tell me the reason for which he didn’t turn up.

3, The professor has assigned the students a research paper whose purpose is to acquaint them with methods of scholarly inquiry.

4, The people whose house we visited were nice.

5, The picture which she was looking at was beautiful.

The picture that she was looking at was beautiful.

6, I liked the composition that you wrote.

@mochizou