天天的英文缩写为every day。

双语例句：

1、这次旅行天天下雨，让我们大失所望。

To our great disappointment， it rained every day of the trip.

2、对他来说似乎天天都一样。

Every day seemed the same to him.

3、随着日子一天天过去，他越来越绝望。

With every day that passed he became ever more despairing.