simple present or present progressive

Here are a lot of exercises about the difference between simple present and present progressive.

http://www.ego4u.de/de/cram-up/grammar/simpre-prepro/exercises
http://www.ego4u.de/de/cram-up/grammar/simpre-prepro/exercises?ex08
http://www.ego4u.de/de/cram-up/grammar/simpre-prepro/exercises?ex12
http://www.englisch-hilfen.de/uebungen/zeiten/simple_present_progressive2.htm
http://www.englisch-hilfen.de/uebungen/zeiten/simple_present_progressive.htm
http://www.schule-bw.de/unterricht/faecher/englisch/mat-med/grammatik/tenses/prescontrast/spprog1.htm
http://www.schule-bw.de/unterricht/faecher/englisch/mat-med/grammatik/tenses/prescontrast/spprog2.htm

the imperative (=Befehlsform)

Train the imperative. Follow the links.
http://www.englisch-hilfen.de/uebungen/verschiedenes/imperativ.htm
http://www.englisch-hilfen.de/uebungen/verschiedenes/imperativ2.htm
http://www.schule-bw.de/unterricht/faecher/englisch/mat-med/grammatik/tenses/imperative/command1.htm

This website explains (=erklärt) the imperative again. There is also an exercise.
http://www.keepschool.de/unterrichtsmaterial/Englisch/Das_finite_Vollverb:_Der_Imperativ-865.html

Questions with do/does

Practice on questions with do/does.
http://www.englisch-lernen-online.de/sprachreise/unit-6-meeting-the-neighbours/bereiche/grammatik-fragen-mit-dodoes/
http://www.learnamericanenglishonline.com/Red%20Level/Writing_Exercises/Ex_1_Present_Tense.html

do or does in sentences and questions

Practices on do/does in sentences and questions. Click the links.
http://www.englisch-hilfen.de/en/exercises/tenses/do_does.htm
http://www.englisch-hilfen.de/en/exercises/tenses/do.htm
http://www.englisch-hilfen.de/en/exercises/tenses/do2.htm
http://www.englisch-hilfen.de/en/exercises/tenses/do3.htm
http://www.englisch-hilfen.de/en/exercises/tenses/do_does.htm
http://www.englisch-hilfen.de/en/exercises/tenses/do_does2.htm
http://www.englishexercises.org/makeagame/viewgame.asp?id=1925
http://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-16257.php

countable and uncountable nouns

Practice countable and uncountable nouns.
http://www.myenglishpages.com/site_php_files/grammar-exercise-countable-uncountable-nouns.php
http://a4esl.org/q/j/ck/ch-countnouns.html
http://www.1-language.com/englishcourse/unit9_grammar_exs.htm

http://www.kico4u.de/english/uebungen/paitcher/countable.htm
Drag (=ziehen) the words into the corect box - countable or uncountable?

adverbs of frequency

Click the links and train the adverbs of frequency.
http://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adverbs_of_frequency.htm
http://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adverbs_of_frequency1.htm
http://www.ego4u.com/en/cram-up/grammar/word-order/exercises?11
http://esl.lbcc.cc.ca.us/eesllessons/adverbfreq/adfreqz.htm
http://perso.wanadoo.es/autoenglish/gr.frequ.i.htm

prepositions of place

Click the links and practice prepositions!
http://www.ego4u.com/en/cram-up/grammar/prepositions/exercises?07
http://www.perfect-english-grammar.com/prepositions-of-place-exercise-1.html
http://www.ego4u.com/en/cram-up/grammar/prepositions/exercises?08
http://www.ego4u.com/en/cram-up/grammar/prepositions/exercises?09
http://www.ego4u.com/en/cram-up/grammar/prepositions/exercises?10
http://www.ego4u.com/en/cram-up/grammar/prepositions/exercises

pronoun training

Click the links and then fill in the correct pronoun. You can check your answers, too.
http://www.kico4u.de/english/uebungen/praeposition/dayprep.htm
http://www.kico4u.de/english/uebungen/5klasse/mehimher.htm
http://www.kico4u.de/english/uebungen/5klasse/waskommtrein.htm
http://www.kico4u.de/english/uebungen/pronomen/its.htm

Train the present progressive.

Follow the link, play the game and practice the present progressive. The boy shows you the infinitive (=Grundform) of the verb. Write the present progressive in the box and press ENTER.
http://elt.oup.com/student/englishfile/preint/i_games/gotoschool/games_gts01?cc=global&selLanguage=en