问题
选择题
“Isn’t it about time you _____ to do morning exercises？” “Yes, it is. Would you like to join us？”
A．begin
B．have begun
C．began
D．had begun
答案
答案：C
.It’s time… / It’s high time… / It’s about time… 等后接从句时，从句谓语通常用过去式。