Unless ________ to answer questions, the pupils won't talk in Mrs Smith's class.
A．asking B．asked
C．being asked D．having asked
—Where did you pick up the stamp?
—It was at the post office ________ we worked in the summer vacation.
A．that B．where
C．which D．when
Who ________ that played a trick on the new English teacher?
A．it was B．was it
C．he was D．was him
Where do you think ________ we can buy that bestseller?
A．it is that B．is it that
C．that D．it
There is no doubt that eating organic food will make you healthier, ________？
A．will it B．does it
C．is there D．is it
It was today's activity ________ let me know the importance of teamwork.
A．where B．which
C．that D．what
