why didn't she come?Did you know?合并为一句话.

why didn't she come?Did you know?合并为一句话. How did she come here yesterday?I don't know.(合并为一句) ---Alice,why didn't you come yesterday? Alice,why didn't you come yesterday? 定语从句do you know the reason why he didn't come? Do you know the reason why/for which he didn't come?这句话的意思? 改错--Mary didn't come,did she?--Yes,she comes. She didn't come to school yesterday.Do you know__her?A.why d Have you helped a men You didn't know him.（合并为一句） Have you helped a man?You didn't know him.(合并为一句） 定语从句do you know the reason why he didn't come?为什么可以用why?从句后h Has she visited the Great wall I didn't know.（合并为一句）= I didn