单项选择题
Only then（）how much damage had been caused.
A.she realized B.she had realized C.had she realized D.did she realize
单项选择题 They are the principles, many of them, （）I learned at my mother’s knee.
单项选择题 The question is not worth（）again and again.
单项选择题 How much control you want to turn over to the car may depend on your age and（）.
