I can speak English and some Chinese.

我能够说英语和一些汉语。

youdao

Now I can speak English like an American.

现在我英语说得像美国人一样。

youdao

If I do that, I can speak English fluently.

如果我做到这些，我可以说一口流利的英语。

youdao

I know you can say it easily. I know you can speak well and write well in English. Keep it up!

相信你很快就能掌握的。你的口语跟写作都会很棒的。再接再厉！

I'd better 课堂 - SpeakingMax英语口语达人

and I can speak to him in English.

跟他说英语。

必须掌握两门语言 - SpeakingMax英语口语达人

And Mr Buckles admitted: "I can't say categorically that all the guards recruited by G4S for the Olympics are able to speak fluent English".

BBC: G4S 'regret' over Olympic staffing