What's the difference between 'think' and 'think of'?
I used to think 'THINK + that S+V' and 'THINK OF + N'. But there are exceptions like these.
1. The referee has to think the way the players do.
2. I'm trying to think positive thoughts.
I got confused. And I really need your help.
As a rule of thumb, you could say that when "think" is factitive, it doesn't take an 'of': you think of an umbrella, but think [no "of"] a thought. (This rule of thumb breaks down in cases like "Quiet, I'm trying to think of something" (where the "something" can - but needn't - be an original thought), but it works for "think a thought" and for several of the phrasal verbs that use think - to "think something through/out" and "think about something".