only by constant practice can you learn
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it itIt is (was)that(who/whom)Anne had a severe heart attack last night.? It was Anne that had a severe heart attack last night.() It was a severe heart attack that Anne had last night.?() It was last night that Anne had a severe heart attack.() It is Chairman of the committee that they elected him.?() It was because she was ill that she didn't go to school yesterday.?() it 1.?thatwho It is a policeman who (that) my son wants to be. 2. It is he(him)that is to blame.