I don‘t know how soon he will come back

I don‘t know how soon he will come back I don't know when he _(come)back.when he _(come)back,I will Don't worry,I will come back ()[quickly,soon]. ----How soon will he come back? I don't know （） come back soon. （）back ,I‘ll let you know will he come back on Sunday?I don't know.（合并为一句） I don’t know when it is that he will come back. I don't know if he will ___（come）back.If he___（come）please t I don't know when he ＿（come）back. I don't know if he will come tomorrow. how soon will he come back的回答 初中英语选择题how soon will he come back?