I don't think that ————（watch）TV is a best way to study English.填watch的适当形式,

I don't think that ————（watch）TV is a best way to study English.填watch的适当形式,
I don't think that ————（watch）TV is a best way to study English.填watch的适当形式,

I don't think that ————（watch）TV is a best way to study English.填watch的适当形式,
填watching
这是that引导的宾语从句,作think的宾语.因为填空的部分是从句的主语,所以要选择动名词形式.