B1–B2

Mixed Tenses — English Grammar Exercises

I did vs I have done — finally get it right

Mixing Present Perfect and Past Simple

Real English constantly moves between present perfect and past simple, sometimes within the same sentence. According to analysis of the ICLE (International Corpus of Learner English), tense-switching errors — using present perfect where past simple is required and vice versa — are the most persistent error type across B1 and B2 writing samples, persisting even after learners have studied the individual rules. The key is understanding that the two tenses serve different communicative functions that often coexist.

The Core Principle

Present perfect = past action viewed from the present (no specific time, or ongoing connection). Past simple = past action viewed as a completed historical event (specific time given or implied).

Tense Switching in Context

She moved to London in 2019. (specific year → past simple)
She has lived there ever since. (still true now → present perfect)

I have visited Rome. (life experience, no time given)
I visited Rome last year. (specific time added → past simple)

We already ate dinner → ✓ We have already eaten dinner ('already' = present perfect)...
...so we went to the cinema at eight. ('at eight' = specific time → past simple)

Adding or Removing Time Expressions Changes the Tense

Adding a specific past time to a present perfect sentence forces a switch to past simple. Removing the time expression from a past simple sentence often allows a switch to present perfect.

She has finished her degree. (result now, no time) → She finished her degree in 2022. (specific time)

Common Mistakes

✗ I have went to the store yesterday. → ✓ I went to the store yesterday.
✗ I have bought some milk yesterday. → ✓ I bought some milk yesterday.
✗ She lived here since 2015. → ✓ She has lived here since 2015.
✗ She still didn't find a good job. → ✓ She still hasn't found a good job.

Frequently Asked Questions

When do I use present perfect instead of past simple?

Use present perfect (have/has + past participle) when the connection to the present matters: life experience ('Have you ever tried sushi?'), a result relevant now ('I've lost my keys — can you help?'), or an ongoing situation with since/for ('She has lived here since 2015'). Use past simple when you specify a finished time: 'She moved here in 2015', 'I saw him yesterday', 'Did you call last night?'

What is the difference between 'since' and 'for' in the present perfect?

'For' goes with a duration — a length of time: 'for three years', 'for ages', 'for two months'. 'Since' goes with a starting point in time: 'since 2019', 'since Monday', 'since I was a child'. Both appear with present perfect when the situation is still true now: 'I've worked here for three years' (still work there); 'I've worked here since 2019' (same meaning, different framing).

Which words tell me to use present perfect — just, already, yet, ever?

'Just' (= moments ago), 'already' (= earlier than expected), 'yet' (= up to now, used in questions and negatives), and 'ever/never' (= at any time in your life) are all strong signals for present perfect. Contrast these with past simple signals: 'yesterday', 'last week', 'in 2020', 'two hours ago', 'when I was a child' — any expression naming a finished period forces past simple.

What is 'have been to' vs 'have gone to'?

'Have been to' means visited and returned: 'I have been to Paris three times' (I'm not there now). 'Have gone to' means went and has not returned: 'She has gone to Paris' (she is still there). This distinction is one of the highest-frequency errors in learner corpora at B1–B2 level.