17. Look at this bird-house. Mike has made it himself. He made it last Sunday. 18.Where have you put my pen? I cannot find it. 19. Have you seen Mary today? 20. When did you see Mary? - I saw her last week. 21. Have your mother promised to take you to the theatre? 22.Look at my new dress! I have made it myself. 23.He is not at school today, he has fallen ill.-When did he fall ill?-He fell ill yesterday.
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