问题

Since the time humankind started gardening, we _ _ to make our environment more beautiful.
A:try
B:have been trying
C:are trying
D:will try
B:have been trying
C:are trying
D:will try
正确答案是:
同类题型
When lost in work , ______ he often was , he would forget all about eating and sleeping
Can you understand me, Tony—Yes, madam. You speak _______. I can follow you.
The little girl made money ___ sellingflowers.
-Whatare you going to be when you grow up-I’mgoing to be _____ English teacher in ______ university.
E-mail, as well as the telephone, _____an important part in daily communication.