Nick Jobe is pursuing a degree in English with secondary teaching certification and has tutored in the Academic Center since January 2007. He is a writer, novelist, and Fall '07 winner of the Golden Ampersand award. He would also like long walks on the beach if he liked going to the beach… or walking.

Mood: A grammatical category that shows the degree of certainty carried by the verb's action.  There are four such degrees:
indicative: stating
interrogative: asking
imperative: commanding
subjunctive: expressing a wish or hypothetical statement.

Quoted from Smith and Bernhardt's Glossary in Writing at Work: Professional Writing Skills for People on the Job

Last week's grammar tip discussed the indicative and the imperative moods. This week we'll discuss the subjunctive mood. The subjunctive mood expresses a condition that is contrary to the fact, belief, or expectation of the speaker or writer (Kolln, 135).  The mood is often denoted by an if-clause and avoids the –s form of the verb (were instead of was or had instead of has).

If-Clause: In the case of subjunctive mood, an if-clause will always be in the past perfect form. That means it will include words such as were or had before the verb. An If-Clause is a clause that begins with the word if, such as if this happens, then that happens. (Note: If-clauses may signal the subject mood, but not all if-clauses do so.)

Ex. If Bob were on Mars, he would see Martians.

Notice that the verb in the example sentence is were. The verb form lets us know that Bob, in fact, was not on Mars.

The following examples would not be considered subjunctive mood:

Ex. Since Bob was late, his appointment expired.

Ex. If Bob was invited to the Harry Potter-themed party, he will have had a marvelous time.

The verb was signals the reader that these examples are not in the subjunctive mood.  In the first example, this verb indicates that the event really has already actually occurred: the mood is indicative. The subjunctive mood doesn't apply in the second sentence because it suggests a possibility.  The possibility discussed (Bob's attendance at the party) is not contrary to the fact, belief, expectation of the writer, rather the second example is a statement about the belief or expectation of the writer.

The subjunctive mood also often denotes a wish.

Ex. I wish he were here, then we could have some fun.

This example sentence denotes the subjunctive mood because it uses the verb form were and uses I wish at the beginning, both of which show that the action has not actually occurred.

Like was and were, has and had, when used as helping verbs, can also be used to express or not express the subjunctive mood.  The following example, which uses had, denotes the subjunctive mood:

Ex. Had I known the truth, the Martians might not have taken Bob.

Note that had I known the truth can also go at the end of the sentence or in the middle of the sentence, as well:

Ex. The Martians might not have taken Bob, had I known the truth.
Ex. The Martians, had I known the truth, might not have taken Bob.

However, like was, has does not denote the subjunctive mood, as shown in the following: 

Ex. Bob has been abducted.