It useful for individual words but there is some problems with sentences.

no grammar

Quite a bad one . I recommend you to look for others alternative to translate Arabic-English.

I used google translate for a long time and it is helpful for translating words but of course u can never trust it to translate sentences.. there is an alternative website as an arabic dictionary - almaany.com// it can help also.

Machine translation is notoriously poor partly because it can be fooled. For many months, I could demonstrate that Google translated perfectly good Arabic into Angry Bird's Birthday Party.