Test yourself with different exercises in the following topics:

present simple – I work at Lexis Languages
present continuous – I am working on a presentation this week
present simple v present continuous
to be (past form) – I was in Berlin last week
past simple – I worked in Bremen last week
do/did – Where do you work
past continuous – I was working at 11am yesterday
past simple v past continuous
future with ‘going to’ & ‘will’ – I’m going to London tomorrow
present perfect (have, ever & before) – Have you ever been to London?
present perfect – (for & since) – I’ve lived in Bielefeld since 2003
past simple v present perfect