The word “commensurate” means that something has a suitable value in realtion to the value provided. You use “commensurate” with the preposition “with” to connect the two things we are comparing in value.
The amount of work required is commensurate with the salary provided.
We use the preposition “with” with a verb or adjective when we mean “in relation to”. This is exactly the situation for the adjective “commensurate”.
I hope the punsihment is commensurate with the crime.
Commensurate + No preposition
We can also use “commensurate” without a preposition. We do this when the object of “commensurate” is implied or obvious.
I hope the punsihment is commensurate.