Could someone help me to understand when I should use think of and when think about in sentences?
What is the difference between using one or the other?
I'm trying to think of a context where there is a difference, and it's very hard to do that. What makes this tricky is that the two are pretty much interchangeable in many contexts:
When I think about/think of my mother, who passed away three years ago, I get very sad.
but there are other occasions when one would be slightly (or clearly) favored over the other:
I get excited when I think about football season getting underway.
I can think of 10 reasons why you shouldn't text and drive.
And then there's this gem:
I can't think of it right now, but maybe I will, if I think about it long enough.
If I had to summarize, I'd say that think of seems to mean recalling something specific, while think about seems to mean considering some subject in a more vague or general way for some length of time. The two are sometimes interchangable because there are many situations where you can't think about something without also thinking of it, such as when you are fondly remembering your deceased mother.
This is a great question; I hope others weigh in. I think I might be getting close to something here, but I'm not convinced I've nailed it.
Adding to the answer above, "think of" is often used when we wish to express an opinion of someone...
either without actually doing so:
I can't tell you what I think of you.
or with an adverb in-between:
I think badly of him.
I think well of him.
We would not say "I think badly about him" — that would mean that when we think about him we don't think well!
As a language teacher, this is something my students ask me a lot. So, I have researched this topic the best way I could, which is by using Corpora (an analysis of millions of texts in English). I did this in order to give the best answer I possibly could, because being a native speaker was not enough to put everything in order. Here's what I found.
Compared to the previous posters, some of what is said is true and other is not. So both of these are actually equally frequent in their use, around 80,000. Mostly, these have very different meanings, except one case, which is giving an opinion (see below). The frequency of this use case, however, is not so high ("what do you think about/of"+"what you think about/of" is 4-5% of total use cases.
Summary:
Think of (Meaning: bring something into your mind) Use cases: • New ideas • Reminder of people or things • Brainstorming • Finding solutions • Giving an opinion (About 5% of total use cases)
Think about (Meaning: concentrate and focus on something) Use cases: • Concentrating on a topic, person or action • Taking a person into consideration • Memories and experiences • Giving an opinion (About 4% of total use cases)
Examples of common phrasing:
“Think of someone who helped you.” = Search through your memories.
“California is an agricultural state and so many people don't even think of it that way.” = Consider something as something, an opinion.
“And that's a funny thing, when you come to think of it.” – when it enters your mind.
“What do you think of her?” = Invitation to give an opinion
“Think about it. It’s a great idea.” = Give it consideration and contemplation.
“I want you to think about your daughter who loves you before you make this decision.” = Keep her in consideration.
“You're not a kid anymore. You have to think about your future, Jess.” = Keep it in consideration.
“What do you think about that?” = Invitation to give an opinion
The chosen answer in this case gives this example of equal meaning: "When I think about/think of my mother, who passed away three years ago, I get very sad."
These sentences have the potential to be equal in meaning but only when combined in this way. Here's the difference:
"When I think of my mother..." = When I am reminded of my mother. In this case, just the though makes me sad. For example, seeing a picture or her favourite TV show, could make make me think of her, and that makes me sad.
"When I think about my mother..." = When I concentrate on and contemplate her. In this case, the contemplation and concentration on the topic makes me sad. Just being reminded of her doesn't affect me so much, but really concentrating on the topic does. Just seeing her picture or just seeing her favourite things, wouldn't make me sad. But when I sit and think about her and the time we spent together, it does.
Be careful when analyzing sentences outside their context to determine meaning. The meaning although close, is not the same and clearly implies or requires a different context.
Conclusion
In the majority of cases, (95%) these two have different meaning. It is only when giving opinions that they can be used interchangeably. In some cases, it is easy to see the difference and in some specific situations, if you ignore the context, it is not so easy. Have a look at the summary and the examples in order to see when one should be used versus the other.
For more information have a look at https://www.english-corpora.org/coca/
I'm teaching English in a Senior School as a second language.
With the above examples in mind - -When I say what I think of Raul - I'm meaning that I'll say my opinion in general, about him... not in detail, but -If I say what I think about Raul - I'm meaning that I'll tell some important details I know about him.
[I've just copied this answer in its entirety from my original ELU answer.]
In many contexts, think of and think about are effectively interchangeable...
"They say Greece may leave the Eurozone. What do you think of/about that?"
"I'm thinking of/about looking for a new job"
In other contexts, to think of something means you're at least aware of the thing, but may not have given it a great deal of consideration. If you think about something this normally implies more focussed or extended attention.
"I never thought of doing that!" (that possibility never crossed my mind).
"Have you thought about my birthday present?" (have you considered/decided what to get me?)
Much the same distinction applies to hear of/about. You might say you've heard of something meaning no more than that you're aware "something" exists. But if you've heard about something the implication is you've heard some important/current information about that thing.
"I've heard of Amy Winehouse" (the name is known to me, but I don't necessarily know any more).
"I've heard about Amy Winehouse" (strongly implies knowing of her untimely death).