You'd better not be lying.

It's what's best.

We'd better get to work.

better than I thought

Thank God. It's way better than I thought. / Слава Богу. Это лучше, чем я думал.

I'm better now.

You'd better shut your mouth.

It's best we come clean now.

It might be best if you just let it go.

you best wait

You best wait until the radiation level goes down. / Тебе лучше подождать, пока не снизится уровень радиации.

He thinks he is better than everyone else.