17.have you known-have known-did he do-came-was

18.haven’t seen-hasn’t been-bought

19.has the plumber been-has stayed-did he do-turned-emptied

20.were-was-Did you enjoy-took-Did you win-came

21.How long have the horrible monument been-has been-wrote-has been

22.have just been-Have you seen-haven’t-didn’t read-read-did Tolstoy write-wrote-Did he write

23.brought-did he do-wanted

24.were-was-Did he take-did-Has it hurt

25.said-hasn’t phoned

26.have just received-didn’t pay-Haven’t I given-have-spent

27.have you been-have just started-did you find-answered

28.Have you finished-have done