34．The teacher asked me to practice ________ as often as possible .

　 A．to run　　　　　　 B．run　　　　 C．ran　　　　　 D．running

33．Li Lei was late for school ______ the bad traffic .

　 A．because　　　　　 B．for　　　　　 C．because that　　　　 D．because of

32．It’s about three months ______ he left home .

　 A．for　　　　　 B．since　　　　 C．before　　　　 D．because

31．Look ! The students are walking ______ the school gate .

　 A．with　　　　　 B．on　　　　　 C．through　　　　 D．for

30.I don’t know when to leave.

I don’t know when I ____ _____.

29.The waves in Hawaii are the highest in the world.

The waves in Hawaii are ______ than _____ in _____ _____ ____ in the world.

28.You can’t sing well. I can’t sing well, either.

_____ you _____ I _____ sing well.

You can’t sing well. _____ _____ _____.

27.Whatever happens, don’t open the door.

_____ _____ _____ happens, don’t open the door.

26.It is so difficult a maths problem that we can’t work it out.

It is ____ ____difficult maths problem that we can’t work it out.

The maths problem is ____ difficult ____ us ____ work out.

25.I don’t know when I shall start the work.

　 I don’t know when ____ ____ the work.