Watch the video.
It will help you understand the difference between Present Perfect and Past Simple.
Present Perfect is similar to the past, but with no specific time:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEie2mFN-jsXNzx52Qhlz-MoCme1W60rUvKFw753wiuKf2Fxc5jO8SDpM0PhnndDGeoTveWmsqcWsmnBsRm_hMkfEb8XsYMTLuTrhRbA0AHT773s4LLRInWpmz10OvX8gpJa8PXX8Dg-jvl_/s400/SEM_TT%257E1.JPG)
And it is centered in the experience, not time:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgr4Y4WGCwDOuUWtyY5O4EFKH2XVIG6jnL-6UiMT08vKlm8NMIjgB4SeaLMGujAh5AfThRLWA7S63CD7BSx5DxFkt5fgsaf8kxztyvCKyd3rqChu3cuCTOuUQkL2ZotRaZPgmrsONBod-bV/s400/SEM_TT%257E2.JPG)
Other examples:
PRESENT PERFECT
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiA42j2ViqAXvAmWr8awMAh3u1I5QoiR3z4gecSfQDEjXs6eEGbU1gBWMpl0BcGzyTma94oEmResbpMugkQyKPbCCGj6Mm9hMJA25H7oHoLG-a4Hw7mfYSPigc7nD8yexLDiH3wLxziV6W6/s400/presperf3.jpg)
The PRESENT PERFECT is often used with the following time expressions:
How long...?
...for...
...since...
...just...
...lately
...recently
...ever...
...already...
...never...
...yet...
PAST SIMPLE
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhOg9b4ucOeu4EvECN6J9vWsemxWrKIuWAPr7UuBfve2X9CFPvv-Cc4MZ8MDbjupopCd6m5zCC3AA7Dx0AF2hiXFZvOqT36tAZpIy_KxULL0fhdt8VJcJdbJEhq8F4Sc1NC1l-2mr4NMV8n/s400/spast.jpg)
The PAST SIMPLE is often used with the following time expressions:
... ago
... yesterday
...last week / month / year
...
EXERCISES ON USE: Past Simple or Present perfect?: