英语中,如果复合句中含有时间状语从句、条件状语从句、让步状语从句、原因状语从句时,若主句、从句都是一般将来时,那么为了避免重复,往往主句用一般将来时,从句用一般现在时.
As soon as I get to Beijing ,I will ring you up .
If it is fine tomorrow ,we will go for a picnic in the park .
would 是will 的过去式,如果主句是过去将来时,从句用一般过去时 .
主将从现里will和would的用法