1.With the rapid development of economy,the freeway network in China ____ greatly over the past decades.

1.With the rapid development of economy,the freeway network in China ____ greatly over the past decades.
A.was expanded B.expanded C.has been expanded D.has expanded
2.I did what I could ___ the computer,but is still doesn't work.
A.repair B.repairing C.to repair D.to be repaired
3.With spring ______,millions of insects arrive to attack the farmers'crops.
A.is coming B.comes C.coming D.to come
4.The wife is lazy ____ her husband is hard working.____ he is just over thirty,he looks much older for his age.
A.when;when B.when;while C.while;when D.while;while
5.---Last night when I was watching a horror film at home,the lights went out suddenly.
---Oh,you _____
A.might be frightened B.must have been frightened
C.could have been frightened D.should be frightened