Examples must-be in Czech examples

How do I translate must-be into Czech?

Simple sentences

You must be careful not to make him angry.

Musíš být opatrný, abys ho nerozzlobil.

You must be a fool.

Ty musíš být blázen.

Movie subtitles

Oh, they must be twins.

Dvojčátka.

And then to abandone Richard who she loved. How hard it must be not to die. Take it easy, ma'am.

A ona musela opustit svou životní lásku.

He must be hurt because of me.

Myslím, že jsem mu ublížila.