你好。它们一般都用与主将从现：
If /
as soon as she comes tomorrow,she will tell us about her last week's trip in Japan.
这里的as soon as 和if 都是连接词， 即便它们指代的事物是将来发生的，come这个动词不能用will come,只能用一般现在时。它的主句是
一般将来时或祈使句，如
Come if / as soon as you are free next week.==As soon as / if you are free next week,come.
也有---主过从过----但它必须用于过去时间i( if 这个结构不包括在内）。如,
As soon as I got the news yesterday, I told Tom==== I told Tom the news yesterday as soon as I got it. 请比较以下句子
1 He says that he will come tomorrow if / as soon as he is free.
2 He said that he would come the next day if / as soon as he was free.本回答被提问者采纳