I. 单项选择
1. In our class __________of the st udents are girls.
A. three fifths B. three fifth C. third fi ve D. third fifth
2. Oh，the milk _________strange, do you think it’s OK to drink?
A. was tasted B. tasted C. is tasting D. tastes
3. It’s hard to keep the house ________with th ree kids.
A. cleaning B. to clean C. cleaned D. clean
4. Don’t l eave until he _______back.
A. have come B. comes C. will come D. came
