如果你不来参加聚会，那我也不会去了。

If you don't come to the party, ___then I won't go either.

我们先吃晚饭，然后去看电影。

We'll have dinner first, and ___then go to the cinema.

我先整理房间，然后还要洗衣服。

First I'll clean the room, ___then I need to do the laundry.