Am I using the subjunctive mood correctly?

Does this sentence use the subjunctive correctly?

He spoke as though he was the only one to tell the truth.

Solution 1:

If you want to use the subjunctive, you should use were; if you do not, the mood is not subjunctive:

He spoke as though he were the only one to tell the truth.

Wikipedia's article on the subjunctive mood, in the section entitled To express a counterfactual hypothesis, states:

[T]he past subjunctive is used following the conjunctions as if and as though to express a contrary-to-fact situation that reality is supposed to resemble.

• She looked as though she were going to kill him.

As though can also precede was and still be perfectly correct. Again, grammatically speaking, this would not be in the subjunctive mood. See this forum thread:

There is only one situation that requires the irrealis (subjunctive) form: conditional inversion. Were he weary, he would not be walking so fast. Here "was" is not possible. In all other circumstances, "was" is an acceptable standard alternative to irrealis "were": as though he was already weary of the day is what I would normally say, though I could also use "were". It does not matter how hypothetical or unreal the situation is: that, if it does anything, merely increases the likelihood that the irrealis form is used. It does not make it obligatory.

Solution 2:

The sentence is fine, but that’s not the subjunctive. The subjunctive would use were, not was.

Either one is correct; were is much more formal.

Some people would go so far as to say that only were is correct, but good English speakers and writers use was in this sort of context quite naturally:

Dumbledore did not speak for a moment; he looked as though he was trying to make up his mind about something. At last he said, “I am sure. I trust Severus Snape completely.” —Rowling, J. K., Harry Potter and the Half-Blood Prince, chapter 25