Which sentence is better?
When I am speaking about something happened two years ago .

- I have had to work really hard in high school to get good grades.
- I had to work really hard in high school to get good grades.

And which one is correct ( at high school/ in high school ) ?

Thank you!

Question

Which sentence is better?
When I am speaking about something happened two years ago .

- I have had to work really hard in high school to get good grades.
- I had to work really hard in high school to get good grades.

And which one is correct ( at high school/ in high school ) ?

Thank you!

Answer

The first sentence indicates you are still in high school by saying "have had". Since it happened two years ago, just using "I had" indicates it is something in the past that you did and is finished. And "in high school" is correct.

Answer

Second one is more appropriate .

Answer

The second one sounds more natural to me,  and "in high school" is correct.