In the following questions would you use who or whom. Our grandfather,( )is now 65, competed on thh gymnastics team. No one ( )hss studied gymnastics would say that.

Who is a subject. Whom is an object.

You need a subject in these sentences,
"_____ is now 65 . . ."

"No one ______ has studied . . ."

Then in this sentence That is the teacher whom i like best. Whom would be the direct object ?

Correct

To determine whether to use "who" or "whom" in these sentences, you need to identify whether each pronoun is functioning as the subject (who) or the object (whom) of a sentence.

In the first sentence, the pronoun is referring to the subject of the verb "competed." Since it is the grandfather who is doing the competing, the correct pronoun to use is "who."

Our grandfather, (who) is now 65, competed on the gymnastics team.

In the second sentence, the pronoun is referring to the object of the verb "studied." Since it is no one who is being studied, the correct pronoun to use is "whom."

No one (whom) has studied gymnastics would say that.