ce qui, ce que

Last week's relative pronouns with nothing in front of them. Qui and que point back to a noun; ce qui and ce que point at a whole idea, where English says "what".

Je ne comprends pas ce que vous dites. — I don't understand what you are saying. Dis-moi ce qui ne va pas. — Tell me what is wrong.

The test is exactly the same as last week:

So ce qui est important (the verb est follows) against ce que je trouve important (the subject je follows).

The construction worth memorising as a block, because it is the most useful sentence shape at this level:

Ce qui m'intéresse, c'est la musique. Ce que je préfère, c'est le train. Ce qui me manque, c'est le soleil.

It puts what matters at the front and names it at the end. In an exam it buys you time to think, it sounds far more fluent than j'aime la musique, and the pattern never changes: ce qui/que … , c'est … .

Note the c'est is required. Ce que je préfère est le train is grammatical but nobody says it. The doubled structure — announce, then deliver — is the idiom.

tout ce qui / tout ce que means "everything that": tout ce que je sais, tout ce qui reste.