A: Have you read this book yet?#
B: Yes, I have.#
A: When did you read it?#
B: I read it last year.#
A: Have you done your homework yet?#
B: Yes, I have.#
A: When did you do it?#
B: I did it half an hour ago.#
A: Has he gone yet?#
B: Yes, he has.#
A: When did he go?#
B: He went an hour ago.#
A: Has she spoken to him yet?#
B: Yes, she has.#
A: When did she speak to him?#
B: She spoke to him yesterday.&