She kept practicing ________ she could win the National Speaking Competition.
There are several chemical factories ______ waste water into the river. A. pours B. pour C. pouring
Jim has been to the Great Wall before, ______ he? A. has B. does C. hasn’t
The city has improved a lot _________ I came here a few years ago. A. sinceB. forC. when
The weather in summer here is cooler than ______ in Beijing. A. this B. that C. it
In our class, about ______ of the students are girls. A. three fifths B. third fifth C. third fifths