B1 Intermediate Perfect and past tenses
Present perfect vs past simple
Lesson goal. After this lesson you can choose between the past simple and the present perfect — the hardest tense choice for Vietnamese learners.
When to use it
- Past simple: a finished action with a stated time, or a time both speakers know.
- Present perfect: a finished action with no stated time, or one that still matters now.
- The same event can take either tense, depending on what you emphasise.
Form
| Past simple | Present perfect | |
|---|---|---|
| Form | V2 (went, saw) | have/has + V3 (gone, seen) |
| Time | specific: yesterday, in 2020, ago | not specific: ever, never, before |
| Example | I saw him yesterday. | I have seen him twice. |
| Questions with When | When did you arrive? | ✕ not used with When |
Step by step
- Look for a past time marker: yesterday, last…, ago, in 2020.
- Found one → use the past simple, even if the event still feels relevant.
- No marker → ask: does it still affect now?
- Yes, or you are talking about life experience → present perfect.
One event, two tellings
| Sentence | Tense | Emphasis |
|---|---|---|
| I have lost my keys. | present perfect | I can't get into the house now. |
| I lost my keys yesterday. | past simple | It happened yesterday; it may have been found by now. |
| She has gone to Hue. | present perfect | She is in Hue now. |
| She went to Hue last week. | past simple | The trip is over; she may be back. |
Examples
I have been to Ha Long Bay twice.
I went to Ha Long Bay last summer.
Have you ever eaten sushi?
When did you eat sushi?
She has just finished her report.
She finished her report two hours ago.
Common mistakes
I have seen that film yesterday. → I saw that film yesterday.
Vietnamese marks all past events the same way, so the switch feels arbitrary. Hard rule: a stated time means past simple.
When have you arrived? → When did you arrive?
When asks for a specific time, and the present perfect refuses to name one — they contradict each other.
She has left an hour ago. → She left an hour ago.
ago always takes the past simple.
Memory tip
Before choosing, hunt for a time marker. If there is one → past simple, no further thought. Only when there is none do you have to weigh it up.
Summary
- A stated past time → past simple.
- No time stated, experience or a result that still matters → present perfect.
- When…? always takes the past simple.
Practise this lesson
Do exercises with an explanation for every question, take mini tests and track your progress on GrammUp.