2 sentences

1. 海啸应该已经退去了才对。

   hǎi​xiào yīng​gāi yǐ​jīng tuì​qù le cái duì.

   The tsunami should have receded by now.

   Source: OpenSubtitles

2. 潮水渐渐退去了。

   cháo​shuǐ jiàn​jiàn tuì​qù le.

   The tide gradually receded.

   Source: Dong Chinese Dictionary