please correct the following sentences which i have taken from past papers.

1.when i went theree he was watching television since a long time.

2.he said that he was a student of the college for the last two years.

3.I saw him in the morning of twele december.

4.How long do you know him.

5.as every body knows that we pakistanies have not been able to manage our affairs successfully.

6.i would be grateful if you kindly help

7. i was informed by the security guard the manager left five minuts ago.

8.hardly he passed the examination he recieved a good job offer.

9.can you tell me that how can i learn english quickly.

10.when i reached at the station he was waiting for me at the platform the last two hours.