The two most common prepositions used after the verb "think" are "about" and "of." They are very similar, but there is a small difference.
Usually when you think of something, it is a brief moment - just a few seconds. It is also used for opinions. When you think about something, you are considering it for a longer time - like a few minutes or more.
Every time I hear this song, I think of my mother.
(thinking for a few seconds)
What do you think of my new haircut?
I'm thinking about moving to a different city.
I still get angry when I think about all the rude things my sister said to me. (thinking for a few minutes or more)
Common error: Don't use "think to" for "considering."
I'm thinking to do an intensive English course in Canada.
I'm thinking about doing an intensive English course in Canada.
In this classic 80s film which made Karate a major trend among youngsters we hear again and again how kicking your opponent in the face is illegal and won t be tolerated by the tournament s officials. However, Daniel san beats Jonny in the final with the legendary crane kick to the face, becomes a champion, and gets the girl too. So what? Just a minor little detail as long as it s the good guy doing the face smashing, right?