Hi there, everyone!
Here are some sites you may use to improve your skills. Present Simple and Present Continuous exercises with check button! Enjoy!!!

http://web2.uvcs.uvic.ca/elc/studyzone/330/grammar/simcon1.htm
http://www.englishpage.com/verbpage/verbs1.htm
http://englishlearner.com/tests/present_simple_continuous_quiz_1.shtml
http://www.inglesonline.com.br/exerciciosdeinglesonline/simple-contpresent1.htm