Unit 2: Tenses

I. Orientation

A tense is a grammatical form that locates an action, event, or state in time. English has three basic time references—present, past, and future—and each may be expressed through simple, continuous, perfect, or perfect continuous forms. Tense also shows whether an action is complete, continuing, repeated, or connected with another time.

• Time reference: Present relates to now or regular time; past relates to an earlier time; future relates to a later time.
• Aspect: Simple presents facts or complete events; continuous presents activity in progress; perfect presents an earlier action connected with a later point; perfect continuous emphasizes duration.
• Auxiliary verbs: Forms such as be, have, and will help construct tenses and questions.
• Subject–verb agreement: A singular third-person subject generally takes -s or -es in the present simple: She works.
• Time expressions: Words such as every day, yesterday, now, already, and tomorrow help identify the intended tense.
• Meaning before form: The speaker’s intended meaning determines the tense; a time word alone does not always determine it.

II. Present Tenses — Events connected with now

Present tenses describe current states, repeated actions, actions happening around the present, and past actions whose results remain relevant.

A. Rules of present tenses

The rules of present tenses depend on whether the sentence expresses a habit, an activity in progress, a completed action connected with the present, or duration continuing to the present.

• Present simple rule: Use the base verb with I, you, we, and they, but add -s or -es with he, she, and it: They read; He reads.
  • Spelling: Add -es after -s, -sh, -ch, -x, or -o: watches, goes. Change consonant + y to -ies: studies.
• Present continuous rule: Use the present form of be plus the present participle: am/is/are + verb-ing. It normally describes an activity in progress.
• Present perfect rule: Use has/have + past participle. Has follows a singular third-person subject; have follows other subjects.
• Present perfect continuous rule: Use has/have been + verb-ing to emphasize an activity continuing up to now: She has been working.
• Stative verbs: Verbs such as know, believe, own, and understand usually appear in the simple form, not the continuous form: I know the answer, not normally I am knowing.

B. Usage of present tenses

Present tenses are selected according to the action’s regularity, duration, completion, or connection with the current situation.

• Present simple usage: It expresses habits, routines, facts, permanent situations, and timetables.
  • Concrete examples: The sun rises in the east states a fact; The lecture begins at 9:00 describes a scheduled event.
• Present continuous usage: It expresses an action happening now, a temporary situation, or a fixed future arrangement: The students are writing now; I am meeting the dean tomorrow.
• Present perfect usage: It expresses an unspecified past action with a present result, or an action in an unfinished time period: She has lost her key; We have completed two units this week.
• Present perfect continuous usage: It emphasizes duration or repeated activity from the past until now: They have been studying for three hours.
• Signal expressions: Usually and every Monday commonly support the simple form; now supports the continuous form; already, just, and yet commonly support the perfect form.

C. Formation of present tenses

Present-tense formation follows predictable patterns for affirmative, negative, and interrogative sentences.

• Present simple formation:
  
  TEXT

    Affirmative: Subject + base verb / verb-s
    Negative: Subject + do/does not + base verb
    Question: Do/Does + subject + base verb?

  
  Does she work? is correct because does carries the third-person marker, so the main verb remains work.
• Present continuous formation:
  
  TEXT

    Affirmative: Subject + am/is/are + verb-ing
    Negative: Subject + am/is/are not + verb-ing
    Question: Am/Is/Are + subject + verb-ing?

  
  Example: Are they waiting outside?
• Present perfect formation:
  
  TEXT

    Affirmative: Subject + has/have + past participle
    Negative: Subject + has/have not + past participle
    Question: Has/Have + subject + past participle?

  
  Example: Have you finished the report?
• Present perfect continuous formation: Use has/have not been for negatives and place has/have before the subject in questions: Has he been reading?

III. Past Tenses — Events before the present

Past tenses locate events before the moment of speaking and show whether those events were completed, ongoing, or related to another past event.

A. Rules of past tenses

Past-tense rules distinguish a finished past event from an activity in progress or an earlier event connected to a later past point.

• Past simple rule: Regular verbs generally take -ed: walk/walked. Irregular verbs change differently: go/went, write/wrote.
• Past continuous rule: Use was/were + verb-ing. Was follows I, he, she, and it; were follows you, we, and they.
• Past perfect rule: Use had + past participle for an action completed before another past action: The train had left before we arrived.
• Past perfect continuous rule: Use had been + verb-ing to emphasize duration before a past point: He had been waiting for an hour.
• Negative and question rule: Use did with the base verb in past simple negatives and questions: She did not go and Did she go?, not did went.

B. Usage of past tenses

Past forms communicate completed events, background activities, sequence, and duration before another event.

• Past simple usage: It describes completed actions at a definite past time, successive events, and former habits: The committee met yesterday; He opened the door and entered.
• Past continuous usage: It describes an action in progress at a particular past time or background action interrupted by another event: I was sleeping when the phone rang.
• Past perfect usage: It clarifies which of two past events happened first: She had submitted the form before the office closed.
• Past perfect continuous usage: It highlights how long an activity had continued before another past event: They had been travelling for six hours when the bus stopped.
• Time expressions: Last year, two days ago, and in 2019 commonly indicate past simple; when and while often introduce relationships involving past continuous.

C. Formation of past tenses

Past-tense forms are built with either a changed main verb or auxiliary verbs followed by a participle.

• Past simple formation:
  
  TEXT

    Affirmative: Subject + past form
    Negative: Subject + did not + base verb
    Question: Did + subject + base verb?

  
  Example: Did they attend the seminar? The main verb is attend because did marks the past.
• Past continuous formation:
  
  TEXT

    Affirmative: Subject + was/were + verb-ing
    Negative: Subject + was/were not + verb-ing
    Question: Was/Were + subject + verb-ing?

• Past perfect formation:
  
  TEXT

    Affirmative: Subject + had + past participle
    Negative: Subject + had not + past participle
    Question: Had + subject + past participle?

• Past perfect continuous formation: Use had been + verb-ing: They had not been listening; Had she been working?

IV. Future Tenses — Events after the present

Future forms express predictions, intentions, decisions, arrangements, scheduled events, and activities that will be completed or continuing later.

A. Rules of future tenses

English expresses future time through several structures rather than one universal future ending.

• Future simple rule: Use will + base verb for predictions, promises, offers, and decisions made at the moment of speaking: I will help you.
• “Be going to” rule: Use am/is/are going to + base verb for prior intentions or predictions based on present evidence: Look at those clouds; it is going to rain.
• Future continuous rule: Use will be + verb-ing for an action in progress at a specified future time.
• Future perfect rule: Use will have + past participle for an action completed before a future deadline.
• Future perfect continuous rule: Use will have been + verb-ing to emphasize duration up to a future point.
• Time-clause rule: After when, after, before, until, and as soon as, English normally uses the present form for future meaning: When she arrives, we will begin, not normally When she will arrive.

B. Usage of future tenses

Future structures indicate the speaker’s degree of certainty, the preparation behind an intention, and the relationship between future events.

• Future simple usage: It expresses predictions, promises, offers, and spontaneous decisions: I will answer the question.
• Going-to usage: It expresses a planned intention or evidence-based prediction: They are going to build a library.
• Future continuous usage: It presents an activity as ongoing at a future time: At 8 p.m. tomorrow, I will be attending the conference.
• Future perfect usage: It presents an action as finished before a future point: By Friday, she will have completed the assignment.
• Future perfect continuous usage: It emphasizes duration: By June, he will have been teaching for ten years.
• Present forms with future meaning: Present continuous can express a definite arrangement—We are travelling on Monday—while present simple can express timetables—The bus leaves at six.

C. Formation of future tenses

Future forms use auxiliaries or present forms combined with future context.

• Future simple formation:
  
  TEXT

    Affirmative: Subject + will + base verb
    Negative: Subject + will not + base verb
    Question: Will + subject + base verb?

  
  Will you attend the meeting? uses will before the subject.
• Going-to formation: Use am/is/are going to + base verb: She is not going to resign; Are they going to participate?
• Future continuous formation: Use will be + verb-ing: This time tomorrow, we will be flying.
• Future perfect formation: Use will have + past participle: By noon, the workers will have repaired the bridge.
• Future perfect continuous formation: Use will have been + verb-ing: By July, I will have been living here for a year.

V. Imperative negative — Commands expressed in the negative

A negative imperative tells someone not to perform an action, usually to give a prohibition, warning, or instruction.

A. Imperative negative

The standard negative imperative is formed with do not or the contraction don’t followed by the base verb.

• Basic formation:
  
  TEXT

    Do not/Don't + base verb

  
  Do not touch the equipment means that touching is prohibited.
• With “be”: Use Don’t be + adjective/noun: Don’t be careless; Do not be late.
• With “let”: To prohibit an action involving another person or group, use Let + object + not: Let him not enter is formal; Don’t let him enter is more natural.
• Politeness: Add please without changing the structure: Please do not open the window. The imperative has an understood subject, usually you.
• Purpose: Negative imperatives can express safety instructions—Don’t run in the laboratory—or advice—Don’t worry.

VI. Question tags of present, past, and future tenses — Short confirmation questions

A question tag is a brief question added to a statement to seek confirmation or invite agreement. Its auxiliary and tense must match the statement.

A. Question tags of present, past, and future tenses

The general rule is to use a positive tag after a negative statement and a negative tag after a positive statement.

• Present simple tags: Use do/does: You like music, don’t you?; She works here, doesn’t she?
• Present continuous tags: Repeat am/is/are: They are waiting, aren’t they?
• Present perfect tags: Repeat has/have: He has finished, hasn’t he?
• Past simple tags: Use did: They visited Delhi, didn’t they?; She didn’t call, did she?
• Past continuous tags: Repeat was/were: You were listening, weren’t you?
• Past perfect tags: Repeat had: He had left, hadn’t he?
• Future simple tags: Repeat will: We will meet tomorrow, won’t we?
• Going-to future tags: Repeat the form of be: She is going to attend, isn’t she?
• Pronoun rule: The tag normally uses a pronoun matching the subject: Rita is ready, isn’t she?
• Special form: I am late, aren’t I? is the standard tag, although the statement uses am.
• Meaning and intonation: Rising intonation usually signals a genuine question; falling intonation often signals expected agreement. A tag does not change the tense of the original statement.