from then on从那时起
From then on, the prince and princess lived happily.
从那时起, 王子与公主就幸福地生活在一起。
since then从那时以来
They have been good friends since then.
从那时起他们就一直是好朋友。
then and there当时当地; 当场
He turned down their proposal then and there.
他当场就拒绝了他们的建议。
then what下一步怎么办, 然后怎么办
After we finish this, then what?
我们完成后, 下一步怎么办呢?