Why did Jim’s parents have a serious talk with him one year ago? Because Jim had spent a lot of time on ______ .

One year ago today, young Jim’s parents had a very serious talk with him. (11)They complained that he had spent a lot of time before the TV rather than on his lessons. (12)They knew that he always wanted to have a computer of his own, so (14)they promised him a reward if he gave up TV for one year. (15)After breakfast this morning, (13)his father handed him＄500. Feeling that it was not enough, his mother added two hundred more, "Take it son, you have earned it." Yes, Jim has earned it, the hard way--he has not been near the TV for one whole year and his grades have gone from satisfactory to very good. "Now you can turn the TV on if you wish." "Oh, no. Mum, I can’t wait. I have something important to do right now. Then he rushed out of the house.
Why did Jim’s parents have a serious talk with him one year ago?