Use of who for whom

[Hansman]

Mr. Hans, whom I like, is a teacher.​

Can I use who instead of whom like Mr. Hans, who I like, is a teacher?
I know that who can be used for whom in defining relative clauses like I know the man who(m) you like.
However, I am not sure about use of who for whom in non-defining relative clauses.
What do you native English speakers think? Thank you so much as usual.

 

[5jj]

A purist would say that you should use whom. However, most native speakers would say who.

 

[jutfrank]

It doesn't make any difference whether the relative clause is defining or non-defining.

 

[Hansman]

It doesn't make any difference whether the relative clause is defining or non-defining.

Thank you so much.
Do you mean that whether the relative clause is defining or non-defining, we can use who or whom for the same way, right?
Or do you mean that there is no difference in meaning and grammar in defining relative clasues and non-defining relative clauses?

 

[5jj]

Do you mean that whether the relative clause is defining or non-defining, we can use who or whom for the same way, right?

Yes.

Or do you mean that there is no difference in meaning and grammar in defining relative clasues and non-defining relative clauses?

No.

 

[Holmes]

I know that who can be used for whom in defining relative clauses like I know the man who(m) you like.

In defining relative clauses where it is grammatical to use whom, using that or no relative pronoun at all is also grammatical: "I know the man (that) you like." You actually have four options in defining relative clauses in which whom is grammatical:

1. You can use whom and sound formal.
2. You can use that and sound natural.
3. You can use who and sound natural, while risking appearing slightly uneducated, since who is formally incorrect.
4. You can use nothing at all in the position of the relative pronoun and sound completely natural.

There is only one exception to what I have said above. It is in relative clauses, defining or nondefining, in which who(m) functions as the object of the preposition and that prepositional phrase has been positioned at the beginning of the relative clause. Then you must use whom. If you use who instead, you will appear uneducated. Below, option (f) fails from a grammatical standpoint; (g) and (h) do too, of course. Some standards still exist.

a) This is the man I introduced you to last week.
b) This is the man that I introduced you to last week.
c) This is the man who I introduced you to last week.
d) This is the man whom I introduced you to last week.
e) This is the man to whom I introduced you last week.
f) *This is the man to who I introduced you last week.
g) *This is the man to that I introduced you last week.
h) *This is the man to I introduced you last week.

 

[Tarheel]

Most likely, in my humble opinion:

This is the man I introduced you to last week.

Even that doesn't seem likely unless I have forgotten the person's name.

 

[Holmes]

Most likely, in my humble opinion:

This is the man I introduced you to last week.

Even that doesn't seem likely unless I have forgotten the person's name.

If anyone doesn't find my example natural, or "likely," then think of a sentence with a relative clause that does sound natural to you, one whose relative pronoun functions as the object of a preposition. All my points will apply to the example. The points that I made apply to an infinite number of possible examples.

That said, my example is perfectly "likely" if I'm pointing out an individual to you in a group of people (even in a photograph), one of whom I introduced you to last week, and I wish to remind you of that fact. Thus, there was really no reason for you to diss my example in the first place. The example is perfectly fine.