if you study___,you"ll catch up with ___ A hard enough;the oher Bhard enough ;the other

if you study___,you"ll catch up with ___ A hard enough;the oher Bhard enough ;the other
He had no problem___(wark)out the problem 用适当的形式填空
B 后是 the others 修改上面的B 补充问题的那个最好说出理由