Who - What - Wherehttp://www.geocities.com/pccprep/whwords.htm
Questions - Simple Present 1http://www.geocities.com/pccprep/simp_pr_ques.htm
Questions - Simple Presenthttp://www.englisch-hilfen.de/en/exercises/simple_present_questions.htm
Simple present X present continuoushttp://www.englishpage.com/verbpage/verbs2.htm
Present Continuous X Present simplehttp://www.englishpage.com/verbpage/verbs1.htm
Present Continuoushttp://web2.uvcs.uvic.ca/elc/studyzone/330/grammar/pcont1.htm