Here are some useful links with GRAMMAR and VOCABULARY exercises at different levels:
You don’t need to suscribe. Just browse around the site to find extra practice on grammar, vocabulary, etc
There are also some reading activities.
This site has great videos for BASIC GRAMMAR topics:
If you need to improve your LISTENING COMPREHENSION,
http://www.englishcentral.com/videos#!/index/all/all/easiest/5 (Choose intermediate or advanced)
And here’s a podcast that you can download on your mobile phone.
ONLINE DICTIONARY (very useful for online texts)