I have three sentences in my workbook. They seem to be identical in setup to me except the answers for the first two are Whom and the answer for the third is Who (according to the book). Can anyone tell me why? I'm confused . . . Thanks!!

1. The tennis player WHOM we saw in the clubhouse came in that red van.

2. The Canadian skiers WHOM we saw on the train are staying in that condominium.

3. The quarterback WHO Dad thought would start has sprained his ankle in practice.

They all look like objects to me.
I'm sure someone can explain this better, but this is the practical way I tell others to tell the difference in these types of sentences.

In one and two, think of "we saw him (or them) in the clubhouse"...i.e., the tennis player (or Canadian skiers) whom we saw. That is because, in both sentences, whom is the object of the verb saw.

In 3, think of, "Dad thought he would start as quarterback." In the original sentence, who is the subject of "would start." In both of the other sentences, "whom" serves as an object of "saw."

Luckily, it is easy to avoid the whole issue by saying, "The tennis player we saw in the clubhouse..."

"The Canadian skiers we saw...."

"The quarterback Dad thought would start..."
Basically, who has become an acceptable object in the English language. In fact amongst friends, as native speakers we're often ridiculed for trying to sound 'posh'.

Now to answer your question.

There is a trick, if you can change the word for him/her/them it's 'whom' and if you change it for he/she/they it's 'who'.

If the trick doesn't work for you i.e you dont know if it's he or him then try this - the rule - the subject does an action. Can you have two subjects in a sentence? yes.
Subject 1 = dad. dad thought. Thinking was his action.
subject 2 = the quarterback. The quarterback has sprained his ankle. Spraining his ankle is the action.

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