Hello

You can and you should improve your skills to score above 80% in your semester exams. You can do this by following these rules

1. Read previous years' question papers

2. Presentation: Believe it or not, the presentation of your answer greatly affects your marks

3. Read the question paper properly

4. Don't leave any question unanswered

5. Spare yourself the time to revise the answer sheet

6. Read papers suggested by the teachers: When the teacher asks you to go through a certain reading in the class, make sure you do that 

7. Work on your weak points

8. Save time, save marks: You might not realize it now but the small number of hours that you save, help you in the long run to score good marks. Remember that a mark gained here and a mark gained there, when accumulated take your total percentage higher in any given semester. Don't take anything for granted and you will be able to score those extra marks and get an above 80 per cent you aspire for. 

All the best.