Question

what do the verbs fit, set,and read have in common? a, it will require the addition of a helping verb. b. they keep the same form no matter what tense is used, c, they are pronounced different depending on their use. d, they are all considered regular verbs

Answer 1

What the verbs fit, set, and read have in common is that they keep the same form no matter what tense is used.
You can say - I read a book every day. Or Those pants fit you nicely. Or I set the table often.
And if you want to say all that in the past tense, it would look the same:
I read a book yesterday. Those pants fit him nicely a long time ago. I set the table two days ago.

Answer 2

They keep the same form no matter what tense is used