There used to a clean river in front of my house, but now everything has changed.
—Mrs White always helps others _____ she is very busy. —She is so kind.A. but B. because C. although
—The population of the world ____ still ____ now.—So it is.A. are; growing B. will; grow C. is; growing
—It smells terrible. What has happened here?—Look, there is a chemical factory_____ much waste gas.A. pour B. pouring C. poured
In our class _____ of the students _____ girls.A. two fifths; are B. second fifth; are C. two fifths; is
—Where are Maria and Kangkang?—They _____ England.A. had been in B. have gone to C. have been to