It is you as well as your wife that ______ your son's bad performance at school.
Was it in 1969______ the American astronaut succeeded ______ landing on the moon?
---What do you remember Alexander Graham Bell as? --- ______ inventor of ______ telephone.
---I hear that Mary won the prize of the biology contest. ---______ She was not interested in it at all.
Exciting as its special effects are ______, there is too much violence in the film.
---May I take your order now? ---______.