1. + adjective
This is a simple construction as it works just like English.
President Kennedy was widely mocked for announcing to the world “Ich bin ein Berliner!” I am a doughnut. If he had followed our rule above, and omitted the “ein” he would have been fine:
Ich bin Berliner! = “I am a citizen of Berlin”
The reason for mentioning all of this at all is as a reminder NEVER to use “Ich bin…” as the start of a construction like
I’m moving house on Saturday.
I’m visiting my parents at the weekend.
There is only one present tense in German: the present simple, so the equivalent of the English present continuous doesn’t exist.
Samstag ziehe ich um.
Dieses Wochenende besuche ich meine Eltern.