21.Panda is one ofremaining endangered animals in the world.
A.The; The B.A; a C.The; a D.不填;the
22.We live in a world that is changing fast, onechanges come at what seems to be an ever-increasing pace.
A.Unless B.Once C.Whether D.Although
23.I’m into the video game, it’s hard to think of anything else. All my focus is on finishing the story line.
A.Unless B.Once C.Whether D.Although
24.With the country’s population increasing to 1.3 billion, many of China’s rivers, including the legendary Yellow River,.
A.is drying up B.will be drying up C.had dried up D.are drying up