What verbs make a sentence passive?

The verb "to be" in any of its forms (is, am, are, was, were, been, being) is the key ingredient in a passive sentence. It's combined with the past participle of another verb to create the passive voice.

Here's a breakdown:

* Passive sentence structure: Subject + "to be" verb + Past Participle + (by + object)

* Example: The cake was baked by my grandma.

"Was baked" is the passive verb phrase, formed by "was" (a form of "to be") and "baked" (the past participle of "bake").

Here are some examples of verbs that do not make a sentence passive:

* Active verbs: eat, run, jump, play, write, read, etc.

* Helping verbs: will, can, may, should, have, etc.

Important Note: The passive voice isn't inherently wrong, but it's often considered less direct and can sometimes make writing unclear. Use it sparingly and deliberately.