问题

Ninety teachers and students plant _ trees every year.

A:at a time
B:at times
C:at the same time
D:in the same time;

正确答案是：

同类题型

Many workers were organized to clear away_______ remained of the World Trade Center

Polly observed that she ______ by a tall man in a dark coat when she ______ the faces around her on the train

Tim is a friendly boy and we all like .

ceremony, our headmaster requiredstudents to improve our competitiveawareness in modern society

You don’t know me, do you— ________. Don’t you remember ________ the mountain with us last weekend