"日本語を勉強" -> 勉強 is not a verb by itself, it's a noun that means study. To make it a verb, you have to add する. So you could say:
-日本語を勉強します。- I study/will study japanese.
-日本語を勉強しています。- I am studying japanese.
Or even:
-日本語を勉強できます。- I can study japanese. (meaning that the site makes it possible.).
頑張れ!
July 22, 2014 at 9:05am