When We Use Gleich?

There is also a real word for the verb to equal in German but at least in math we say “is equal“. Now, if gleich in sense of same is used as an adjective before a noun, then of course it gets all the corresponding endings. So there's gleiche, gleichem, gleiches and so on.

What is gleich?

Episodic angioedema with eosinophilia (Gleich syndrome) is a rare disorder characterized by episodes of angioedema and eosinophilia that occur at monthly intervals and resolve spontaneously without therapy.

How do you use Vorbei?

For example, if the something is a meal (=Speise), it is fertig when the cooking and serving is finished. It is vorbei when the eating is finished. So, fertig when ready to happen, vorbei when happened already.