单项选择题
A. the society became more complex B. money was created C. trade appeared D. schools became necessary
A. He uses it to race. B. He uses it to tour. C. He uses it to go to work. D. He uses it to exercise.
A. He is interested in acting. B. He is taking some difficult courses. C. He will go to the rehearsal next Thursday. D. He will participate in the rehearsal