How did you manage to get to school on time you missed the school bus?A. whenB. ifC. onc

问题补充：

How did you manage to get to school on time you missed the school bus?

A. when

B. if

C. once

D. because

答案：

(答案→)A. when

B. if

C. once

D. because

解析：整个句子说得是过去的事，不表示假设，只要排除了once，if，答案就只有A了。