Here's the answer:
“在地铁站见吧”
(zài dì-tiě zhàn jiàn ba)
Watch a real native speaker say it:
Here's how it sounds in a textbook:
You could also say:
- wǒ-men zài dì-tiě zhàn jiàn ba
Fun fact: the hundreds of thousands of people learning Chinese with Memrise get this phrase correct 91.67% of the time!