"I am trying to learn English."
Translation:Ich versuche Englisch zu lernen.
Because just like in English with "to", you need "zu" in German when you have an infinitive clause (Englisch zu lernen). Without the "zu", your sentence sounds like "I try English-learning".
There is a difference though: German doesn't use "zu" with modal verbs, while English sometimes does ("Ich muss dieses Buch lesen" - "I have to read this book." But "I must read this book").
This site does a good job explaining when "zu" and when it isn't, and I suggest you have a look at it. Unfortunately, it only exists in German, but the texts are quite short :)