Tenses
A. Four facts about tense that you should know:
1. Tense and time are not the same.
The word tense refers to the forms of verbs in certain languages (including English of course, but many languages do not have tense). The word time is far more difficult to define, but we all experience it. Time is what we measure with clocks, watches, and calendars, for example.
2. Tense and time are related, but it is not a simple (one-to-one) relationship.
That is, present tense does not always mean present time; past tense does not always mean past time. The following simple present tense sentence does not refer to the present time (unless you happen to be reading this very early in the morning):
The sun rises in the east.
In fact, the relationship between tense and time is quite complex. A past tense verb, for example, can refer to a future time:
If I had an exam tomorrow, I would study tonight.
3. It is impossible to completely describe the English system of tenses in a few pages.
English, like all human languages, is extremely complex and almost infinitely flexible. And, as you probably know, nearly every rule about language has many exceptions. Below you will find descriptions of the major English tenses (predicate verb forms). I’ve tried to give you some basic information about the forms and meanings of the twelve traditional tenses. While I believe everything that follows is correct, I know it is not complete.
4. English has only two true tenses: present & past.
Everything else that is usually referred to as tense is really a combination of tense, aspect (continuous, perfect), and/or modality. I will follow the traditional practice and refer to all of these combinations as tenses. However, if you examine these verb forms carefully, you will see that every one contains either present tense, past tense, or a modal auxiliary.


B. The twelve traditional tenses: All examples below are active; see Passive Sentences for examples of passive verbs.
Forms of the predicate verb below do not always apply to the verb be; however, they do apply to all other English verbs. See Auxiliary Verbs for more information about the verb be.
See Conditional Sentences for some unusual uses of tenses.
See Verbs A-L and Verbs M-Z for explanations and examples of the five forms of English verbs: BASE, +S, PAST, ING, PARTICIPLE.
Many teachers and textbooks use progressive instead of continuous; they are the same (continuous = progressive).


Simple Present
Forms of the predicate verb:
1. BASE (if the subject is I, we, you, they, or any plural)
2. +S (if the subject is he, she, it, or any singular other than I or you)
Meanings & examples:
1. Habitual activity
We study every day.
The class meets every Tuesday and Thursday.
2. Present state or condition (stative verbs only; see Stative Verbs below.)
They seem happy.
He knows we are waiting for him.
3. General truth or natural law
Bears live in the forest.
The sun rises in the east.
4. Planned or scheduled future events
We take a final exam at the end of the term.
The plane leaves at 9:00 AM tomorrow.
5. Future time in adverb clauses (see Adverb Clauses)
Before we take the final exam, we will have to study.
I will call her after I talk to her friends tomorrow.
6. In real and predictive conditional sentence (see Conditional Sentences)


Simple Past
Form of the predicate verb: PAST
Meanings & examples:
1. Completed past action
We studied all day yesterday.
I took the exam early this morning.
2. In imaginative conditional sentences (see Conditional Sentences)


Simple Future
Forms of the predicate verb:
1. WILL + BASE
2. AM/IS/ARE + GOING TO + BASE
Meaning & examples:
Future time
We will have lunch with George tomorrow.
He is going to study in the library after lunch.


Present Continuous (nonstative verbs only; see Stative Verbs below)
Form of the predicate verb: AM/IS/ARE + ING
Meanings & examples:
1. Present time
We are preparing for the final exam.
George is studying in the library right now.
2. Planned or scheduled future events
We are taking a final exam at the end of the term.
The plane is leaving at 9:00 AM tomorrow.
3. To emphasize that a state or action is temporary
Mary is living in California. (She might move soon.)
George lives in California. (Simple present: no change is implied.)


Past Continuous (nonstative verbs only; see