高等继续教育 / 大学英语语法
正确率：100%
题型描述: 单选题
It’s time the children ＿＿＿ how to behave properly.
A.learn
B.are learning
C.learned
D.to learn
It’s time the children ＿＿＿ how to behave properly.
A.learn
B.are learning
C.learned
D.to learn
参考答案：