问题
选择题
I didn’t know ________.
A．when did the plane take off
B．when the plane took off
C．when the plane takes off
D．when does the plane take off
答案
答案：B
特殊疑问词作宾语从句，将特此作为连接词，后接陈述句语序。故选B
搜题请搜索小程序“爱下问搜题”
I didn’t know ________.
A．when did the plane take off
B．when the plane took off
C．when the plane takes off
D．when does the plane take off
答案：B
特殊疑问词作宾语从句，将特此作为连接词，后接陈述句语序。故选B