问题

Only when class began ____that he had left his book at home[ ]

A: will he realize
B: he did realize
C: did he realize
D: should he realize

正确答案是：

同类题型

You can’t imagine her________the invitation without thinking twice.[ ]

TheUnitedNations____in1945.

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To be a good teacher, you ___ be able to hold the attention and interest of your students.

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