English Tenses – Advanced Study Notes
(MIT‑Level, First‑Principles Approach)
Audience: Graduate students in Linguistics, Computer Science (NLP), or Applied English.
Goal: Master the formal, semantic, and syntactic underpinnings of English tense, and understand edge cases that challenge naïve textbook rules.
1. Introduction: Why Tense Matters
| What | Why |
|---|---|
| Temporal reference | Indicates when an event occurs relative to a reference time. |
| Aspectual nuance | Communicates how the event unfolds (completed, ongoing, habitual). |
| Discourse function | Regulates information flow, narrative structure, and evidentiality. |
English tense is not a single grammatical property; it is the interaction of three layers:
- Temporal semantics – the mapping from verb forms to time points/intervals.
- Syntactic morphology – the combinatorial rules that attach tense morphology to lexical verbs.
- Pragmatic selection – speaker’s choice based on discourse needs (e.g., future perfect to signal planning).
2. First Principles: Temporal Semantics
2.1. Event Time (ET), Reference Time (RT), and Speech Time (ST)
- ET: The time interval during which the event actually occurs.
- RT: The time point or interval that the clause is anchored to (e.g., the time of speaking, a past reference point, or a future horizon).
- ST: The actual moment of utterance.
| Tense | ET relative to RT | RT relative to ST |
|---|---|---|
| Past Simple | before RT | before ST |
| Present Simple | at RT | at ST |
| Future Simple | after RT | after ST |
| Past Perfect | before RT | before ST |
| Present Perfect | before RT | at ST |
| Future Perfect | before RT | after ST |
| Past Continuous | during RT | before ST |
| Present Continuous | during RT | at ST |
| Future Continuous | during RT | after ST |
Key Insight: The lexical verb’s canonical ET is usually before RT (past) or after RT (future). Tense morphology shifts the RT relative to ST.
2.2. Aspectual Types (Baker 1979)
Aspectual classification (Durative, Achieved, Accomplished, etc.) interacts with tense to produce the tense‑aspect matrix:
| Aspect | Definition | Example |
|---|---|---|
| Finite (S) | Entire event seen as a whole. | She sang. |
| Durative (D) | Ongoing, not yet complete. | She was singing. |
| Accomplished (A) | Completed within a duration. | She sang. (also achieved via has sung). |
| Unaccomplished (U) | Ongoing without completion. | She is singing. |
| Tense | Aspect | Semantic Combination |
|---|---|---|
| Past Simple | S | Past‑S |
| Past Continuous | D | Past‑D |
| Past Perfect | A | Past‑Perfect‑A |
| Present Perfect | A | Present‑Perfect‑A |
| Future Perfect | A | Future‑Perfect‑A |
Semantics: Tense alone does not determine when the event occurs; it sets relative temporal relations. Aspect determines how the event unfolds.
3. Morphological Construction
3.1. Canonical Verb Forms
| Form | Function | Example |
|---|---|---|
| Base | Infinitive/Present | to sing |
| -ed | Regular Past | sang → sang |
| -en | Irregular Past | go → gone |
| -s | Present Third‑Person Singular | sing → sings |
3.2. Auxiliary + Main Verb
The auxiliary system in English is a tense‑aspect interface:
| Tense | Auxiliary(s) | Example |
|---|---|---|
| Present Simple | be (for progressive) or do (for negation) | She sings. |
| Past Simple | did (for negation) | She did not sing. |
| Present Continuous | am/is/are + verb + ‑ing | She is singing. |
| Past Continuous | was/were + verb + ‑ing | She was singing. |
| Present Perfect | have/has + past participle | She has sung. |
| Past Perfect | had + past participle | She had sung. |
| Future | will + base | She will sing. |
| Future Continuous | will be + verb + ‑ing | She will be singing. |
| Future Perfect | will have + past participle | She will have sung. |
Rule: Tense is encoded on the auxiliary; the main verb retains its lexical semantics.
3.3. Morphological Constraints
- Subject‑verb agreement: Only the finite auxiliary carries agreement.
- Negative polarity items: Negation attaches to auxiliaries (did not, has not).
- Wh‑question formation: Auxiliary does or did is fronted (Did she sing?).
4. Semantics–Syntax Interaction
4.1. Temporal Operators
Define two operators:
- P (Past operator) – shifts RT before ST.
- F (Future operator) – shifts RT after ST.
The tense function τ maps a clause C to a temporal relation:
τ(C) = { P(τ(C′)) | C = P C′ }
τ(C) = { F(τ(C′)) | C = F C′ }
Where C′ is the embedded clause.
Example: