You can use Vocabla.com also.

 

 

Reading the news will help. Read BBC, Al Jazeera, CNN. Read the stories in Arabic then again in English.

Find some things you like reading about on the internet. Use google chrome and install the dictionary extension. When you don't know a word just click on it and it will give you a definition.

Thank you Mr conner

I think trying to read a short passage and learn words in context is best. If you want to learn mere words, Memrise or Anki are great ways to learn vocabulary using an SRS system.