question about how to say something

[Miyavifan]

I might one day need to say, "I know only a little Japanese."

Would I say "Watashi wa Nihongo ga tatta sukoshi wakaru.", or "Watashi wa Nihongo tatta sukoshi wakaru.", or neither?
(I thought it was wakarimasu, but my dictionary says it's wakaru)

[01001100]

If someone asks you something like 「日本語が分かりますか」 (do you understand Japanese?), just say 「少し、でもまだ上手じゃありません」 (a little, but I'm not very good yet）.

Edit in case you can't read the above:
にほんごがわかりますか？
すこし、でもまだじょうすじゃありません。

[Miyavifan]

Thank you for replying. Right now I'm using a phone, and it doesn't support Japanese.
I will see what you said, and reply, soon as I'm on a computer. I just didn't want you to think I didn't see your reply.
also, Romaji would be fine, for how to say it, as I'd be saying it in person, not online or anything.
another also. It wouldn't be in response to a question, it would just be if they said something I didn't understand.