1.我长了不少见识。
I've learned something.
The TV show was interesting. (那个电视节目很有意思。)
Yeah, and I've learned something. (是呀，我长了不少见识。)
I've learned something new. (我学到了一些新东西。)

2.那会引起火灾呀!
It's a fire hazard. *hazard表示“人力无法躲避的危险”。
Look at John's toy! (快看约翰的玩具。)
It's a fire hazard. (那会引起火灾呀!)
It could catch on fire easily. (这很容易着火。)
It could cause a fire.

3.什么事都有可能发生。
Anything could happen.
There's no knowing what may happen.
You never know. (任何事情都是很难预料的。)
Anything's possible.
It could happen to you. (对你来说什么都有可能发生。)