42.The man tried to force the locked door open but ().

32.Had he worked harder， he ()the exams.

31.If I ()harder at school， I would be sitting in a comfortable office now.

50.Humble ()it may be， there is no place like home.

49.It is high time that the international community ()together to fight against terrorism.

48.It wasn’t until nearly a month later ()I received the manager’s reply.

47.Scarcely ()when the murderer shot him down.

46.He is the only one of the students who ()a winner of scholarship for three
years.

45.()cleans the blackboard should be praised.

44.He reads newspapers every day to keep himself ()about what’s going on in the world.

43.I fell down and broke three of my teeth.I wonder how many times I have to come
here and get my false teeth ().