The mood of a verb indicates the attitude of the writer. The indicative mood states facts and opinions or asks questions. The imperative mood gives commands and instructions. The subjunctive mood (used mainly in clauses beginning with that or if) expresses wishes or conditions that are contrary to fact.

Subjunctives

The present subjunctive uses the base form, no matter what the subject of the verb is.

It is important that children be psychologically ready for a new sibling.

The past subjunctive is the same as the simple past except for the verb be, which uses were for all subjects.

He spent money as if he had infinite credit.

If the store were better located, it would attract more customers.

The subjunctive mood

Because the subjunctive can create a rather formal tone, many people today tend to substitute the indicative mood in informal conversation.

If I was a better swimmer, I would try out for the team. [informal]

Nevertheless, formal writing still requires the use of the subjunctive in the following kinds of dependent clauses:

Clauses expressing a wish

He wished that his mother were still living nearby.

As if and as though clauses

He started down the trail as if he were walking on ice.

That clauses expressing a request or demand

The job requires that the employee be in good physical condition.

If clauses expressing a condition that does not exist

If the sale of tobacco were banned, tobacco companies would suffer a great loss.

One common error is to use would in both clauses. Use the subjunctive in the if clause and would in the main clause.

Conditional sentences

Sentences that use an if clause don’t always require subjunctive forms. Each of the following conditional sentences makes different assumptions about whether or not the if clause is true.

If you practice writing frequently, you know what your chief problems are.

This sentence assumes that what is stated in the if clause is probably true. Any tense that is appropriate may be used in both the if clause and the main clause.

If you practice writing for the rest of this term, you will understand the process better.

This sentence makes a prediction. The main clause uses the future tense (will understand) or some other modal that can indicate future time (may understand). The if clause uses the present tense.

If you practiced writing every single day, it would eventually seem much easier to you.

This sentence indicates doubt. In the if clause, the verb is past subjunctive, even though it refers to future time. The main clause contains would + the base form of the main verb.

If you practiced writing on Mars, you would find no one to read your work.

This sentence imagines an impossible situation. The past subjunctive is used in the if clause, although past time is not being referred to, and would + the base form is used in the main clause.

If you had practiced writing in ancient Egypt, you would have used hieroglyphics.

This sentence shifts the impossibility to the past; obviously, you aren’t going to find yourself in ancient Egypt. But a past impossibility demands a form that is “more past”: the past perfect in the if clause and would + the perfect form of the verb in the main clause.