Grammar
The verb -be
www.englisch-hilfen.de/en/exercises/tenses/be3.htm
There is/are
www.englisch-hilfen.de/en/exercises/various/there_is_there_are.htm
Possessive adjectives
www.english-area.com/paginas/possessiveadjectives.htm
www.englisch-hilfen.de/en/exercises/pronouns/possessive_determiners3.htm