Do you know __your mother has returned?应该选if还是when

Do you know __your mother has returned?应该选if还是when --do you know the young man with __your father is chatting?AthatBwhichCwhoseDwhom Do you know that I'm Do you know I'm not? I'm waiting for you But do you know?RT - - Husband Do you know i'm waiting for you`? I'm thinking of you 、Do you know 是什么意思 Do you know I.m waitting for you what do you think __your friend A worry about.Bwhat do you think __your friend A worry about.B worries about.C worrying D worries Do you know I'm waiting for you Do you know I'm waiting for you 翻译下 Which do you enjoy __your spare time,reading or playing?应该填不定式还是动名词阿? do you know-G.E.M歌词只要歌词 G.E.M的 do you know 的中文歌词 Do you know.I'm really worried about Can you __your brother__your school? what do you know Do you know what Do you know Facebook?