7.2 Tenses

7.2 Tenses

The Twelve Tense Forms

English verbs combine time (past, present, future) with aspect (simple, continuous, perfect, perfect continuous) to produce twelve tense forms. The PAF English paper tests all twelve, but it weights them unevenly: simple present, present continuous, simple past, present perfect, and future forms dominate. Learn the full grid, then drill the high-frequency cells.

Time Signals: The Shortcut

If you can identify the signal word, you can often pick the tense without parsing the whole sentence.

• since + point in time → perfect: since 0600, since Monday, since 2019.
• for + duration → perfect or perfect continuous: for three hours, for two weeks.
• already / yet / just → present perfect: The cadet has already finished the test.
• ago → simple past only: two hours ago, three days ago. Never has...ago.
• by the time / by + future point → future perfect: By the time we land, the storm will have passed.
• while / when + past clause → past continuous: While the co-pilot was running the checklist, the captain contacted ATC.
• at the moment / now / currently → present continuous: The squadron is currently deployed to the forward base.

Worked Examples

Example 1. The cadet (completed / has completed) the navigation exercise two hours ago.

Signal: ago → simple past. Choose completed. "The cadet completed the navigation exercise two hours ago." The present perfect has completed cannot co-occur with ago because ago fixes the action at a finished past time.

Example 2. By the time the recovery team arrived, the pilot (had ejected / has ejected / ejected) safely.

Two past events; the earlier one needs past perfect. Signal: by the time. Choose had ejected. "By the time the recovery team arrived, the pilot had ejected safely."

Example 3. The base commander (is serving / has been serving) in this role since 2022.

Signal: since 2022 + an action that continues to the present → present perfect continuous. Choose has been serving. "The base commander has been serving in this role since 2022."

Example 4. Look at those clouds. It (will / is going to) rain.

Prediction based on present visible evidence → is going to. "Look at those clouds. It is going to rain." If the prediction were a general forecast with no immediate evidence, will would be acceptable.

Trap 1: Present Perfect vs Simple Past

This is the single most common tense error on the PAF English paper.

• Present perfect (has flown) links a past action to the present. The time is unspecified or unfinished. Use it with since, for, already, yet, just, ever, never, so far.
• Simple past (flew) places the action at a finished, specified time. Use it with yesterday, ago, last week, in 2020, on Monday.

Test: if you can attach a specific past time to the sentence, use simple past. If the time is open or carries to now, use present perfect.

Trap 2: will vs going to

• will — decision made at the moment of speaking, formal announcement, prediction with general evidence: I'll help you with the checklist. The Chief of Air Staff will address the cadets tomorrow.
• going to — prior plan, prediction based on present visible evidence: We are going to deploy the squadron next month. Look at the fuel gauge — it's going to run dry.

A common distractor offers will where the sentence clearly describes a pre-existing plan; the correct answer is going to.

Trap 3: Stative Verbs Cannot Take Continuous Form

Stative verbs describe states, not actions, and are not normally used in continuous tenses even when referring to the present moment. The high-frequency stative verbs on the PAF paper are: know, believe, understand, belong, own, contain, consist, seem, appear, prefer, recognise, matter.

Wrong: I am knowing the answer. Correct: I know the answer.

Reported Speech Back-Shift

When converting direct speech to reported speech, shift each tense one step toward the past.

• "I fly the F-16," he said. → He said that he flew the F-16.
• "I am flying the F-16," he said. → He said that he was flying the F-16.
• "I have flown the F-16," he said. → He said that he had flown the F-16.
• "I will fly the F-16," he said. → He said that he would fly the F-16.

The back-shift is skipped only when the statement is still universally true: He said that the Earth is round.

Back-shift is only the tense half of the transformation. Pronoun changes, time and place words, connectors, and the separate rules for reported questions, orders and exclamations are covered in full in Section 8.5 Direct & Indirect Speech — work that section once you are secure on the tense table below.

Time-Line Diagram

Use a mental time line to place each event. Mark the reference point (now, or a past/future anchor) and draw each action relative to it.

• Past perfect = action before a past anchor.
• Present perfect = action stretching from past to now.
• Future perfect = action completed before a future anchor.

This visual habit resolves the hardest sentence-transformation items in seconds.