Verbs tell you what the subject of a sentence or clause is doing (or being). Verbs are conjugated according to person, number, gender, tense, aspect, mood, or voice.
Verbs are at the heart of sentences and clauses; they are indispensable to the formation of a complete thought. A verb can express a thought by itself (with the subject implied) and be understood.
Action vs. Nonaction Verbs
Action verbs simply indicate an action or occurrence.
Even when used figuratively rather than literally, some verbs can still be considered action verbs.
In this example, the singer didn’t really break anything, but the verb is still an action verb.
Conversely, nonaction verbs can indicate a state of being, sense, emotion, desire, possession, or opinion. The most common nonaction verb is to be.
Verbs change in form, or tense, to indicate whether the actions or states are occurring in the present (or are happening continuously), occurred in the past, or will occur in the future.
These examples indicate the simple present, present continuous, simple past, and simple future tenses respectively. Further possible tenses include present perfect (I have taken the bus), present perfect continuous (I have been taking the bus), past continuous (I was taking the bus), past perfect (I had taken the bus), past perfect continuous (I had been taking the bus), future continuous (I will be taking the bus), future perfect (I will have taken the bus), and future perfect continuous (I will have been taking the bus). All the latter uses would require additional grammatical elements to form complete thoughts. To ensure good writing, it is important for verbs to be used consistently and in a logical sequence so that the time period being written about is properly understood. Verbs can also have up to five different forms: root, third-person singular, present participle, past, and past participle.
Among a verb’s many properties is mood. A verb’s mood, sometimes referred to as a mode, can be either indicative, imperative, or subjunctive. The most common of these is the indicative mood. Indicative mood is used for statements of fact or opinion and to pose questions.
The imperative mood is used to express commands. Subjects are often implied rather than expressed in sentences with imperative verbs. In the following examples, the subject you is implied:
The subjunctive mood is used to express a verb with an action or state that is doubtful, imagined, conditional, desired, or hypothetical.
It is implied by this sentence that you are not actually here, but I wish that were not so. Were is in the subjunctive mood. Conditional verbs (which often appear with if/when statements) also receive a subjunctive treatment.
Were and would run indicate the subjunctive mood.