I can't believe (clause)

You say "I can't believe ___" when a fact is surprising or you want to show that you feel strongly about it. You can say this for positive things:

I can't believe we won!

or you can use it for negative things:

I can't believe you left without telling me.

(something) is cheesy

When you say that something is "cheesy", it means that it's not good because it's too cliché or too over-dramatic. You use "cheesy" to describe movies, TV shows, music, books, etc.

Examples of things that can be called "cheesy" are:

• love songs
• soap operas
• cheap science fiction movies
• romance novels,
• bad jokes

...and so on.

stuff

"Stuff" can mean almost any physical items or material.

It's similar to the word "things", but "things" are countable and "stuff" is not. So "stuff" is better to use when you're talking about a group of things that are different from each other - different sizes, shapes, etc.

"Stuff" is especially used to refer to things that you buy or own:

There's a good chance that you'll end up buying a lot of stuff while you're there.

I'll go pick up all the stuff we need.

Excuse me. Would you mind watching over my stuff for me for just a minute?

But "stuff" can also mean "topics" or "ideas", like in this example:

We have a lot of stuff to talk about.