Ответ:

Положительные:

1.We have bought a new TV set.

2.The students have left the room.

3.The train has just arrived.

4.He has written about a hundred novels.

5.I have already bought that book.

Отрицательные:

1.I have not written the letter.

2.I had not written the article.

3.I should not have written the test work.

4.She hasn't written the test yet.

5.He hasn't phoned this afternoon.

Объяснение:

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