Conditionals with multiple verbs

I'm an ESL teacher. Normally I teach lower intermediate but I also teach a mixed level grammar review class. I pride myself on being able to explain things clearly but today I found myself in THREE sticky situations all in the same class! I'll explain here the two problems involving conditionals.

First Case: Is it better to say...

If he knew that I WERE/WAS home now, he would call. OR If he knew that I AM home now, he would call.

Does the second verb in the if clause also take the subjunctive form because it is in the if clause or should it take the present simple form because it is not a hypothetical (I am home now is not hypothetical, his knowledge of it is.)

Solution 1:

I would write "if he knew that I was home" (with or without "that") because of the sequence of tenses. That is, "knew" is a past tense form, even though it can be either present subjunctive or past indicative. It's therefore ungrammatical to follow it with a present tense form such as "I am" or "I'm". If you were talking in the past indicative, you'd say "He knew that I was home", so you use the same form (adding "if" at the beginning) for the present subjunctive.

Solution 2:

Google Books has 3670 written instances of "if he knew I was here", but only 135 of "if he knew I were here".

As I expected, there are none at all for "...am here", which just sounds like a bad translation to me (though to be fair, there are actually two instances of if he knew I'm here).

Don't bother about "rules" of grammar and logic here - in the long run, it's what people actually say and write that defines "correct".

On the "logic" front, I'll just say I know of no absolute linguistic principle whereby transforming "You know that I am here" into "If he knew that I am here" is guaranteed to produce not only an acceptable form, but the only acceptable form. Anyway, it would be a lousy principle if it pronounced nearly everyone's usage as wrong.

The verb form agrees with knew - so ordinarily, we use the simple past was. A few people use the "subjunctive" were, because the entire conjecture is hypothetical (he doesn't know; the speaker is postulating what would happen if he were to know).

Solution 3:

Am, for the reason you give. Perhaps this will help you explain it:

Tell your class "I know X. Does he?"

There are three possible answers—either

• he does know X or
• he may know X or
• he doesn't know X.

Accordingly:

• (He doesn't know X, but) "If he did know X, he would call."
• (He may not know X, but) "If he does know X, he will call."
• (He does know X, and) "**Because he does know X, he will call."

The same X in every case.

Now, walk your class through it with X = [the name of somebody in the class].

Then do the same thing with X = "that I'm home".

Then substitute "knew" for "did know", and "knows" for "does know" - they probably have sorted those out already.