weil vs denn – both mean "because" – Telc B1

weil introduces a subordinate clause: verb at the end. Er bleibt zu Hause, weil er krank ist. denn connects two main clauses: verb stays in second position in the second clause. Er bleibt zu Hause, denn er ist krank. So: weil + Subject + ... + Verb vs denn + Subject + Verb + .... Don't mix them: after denn the word order is like a main clause.