I've twisted my ankle.

我扭伤了脚踝。

A: What's up? Why are you limping?

A: 怎么了？你为什么一瘸一拐的？

B: I twisted my ankle. It really hurts.

B: 我扭伤了脚踝。很疼。

A: How did you do that?

A: 怎么搞的？

B: It was nothing serious. I just twisted it when I was walking.

B: 没什么大事。是我走路的时候扭伤的。

A: It looks swollen¹. You shouldn't walk on it. You should rest.

A: 看起来肿了。你不应该再用伤脚走路了。你应该休息。

B: I know. I'm going to put some ice on it.

B: 我知道。我要在上面敷些冰。

Notes 注释

1. To ask someone what happened, you can say what's up? or what happened?
要问某人发生了什么事，你可以说What's up? (怎么了?) 或者 What happened? (发生了什么事？)

2. Usually when you hurt your ankle, you say: I twisted my ankle. or I sprained² my ankle.
当你扭伤脚踝时通常可以说：I twisted my ankle. (我扭伤了脚踝。) 或者 I sprained my ankle. (我扭伤了脚踝。)