According to whom
Whose view is this?
Significado
We can present an idea as someone's opinion or belief. This may be the speaker's view or someone else's, and naming it does not mean everyone agrees. Languages use words for thinking, viewpoint phrases, or special markers; some have no separate grammatical marker for this. Certainty shows how sure someone is, whereas this block shows whose view we are hearing.
Como identificar
Look for the person whose opinion, belief, or judgment is being presented, whether it is the speaker's or someone else's.
Na tua língua materna
Acho que and penso que introduce the speaker's view; para mim and na minha opinião can frame a whole statement. Na opinião de and segundo identify someone else's view. Saying whose view it is does not by itself require a special verb form.
Acho que falta sal no arroz.
Para mim, esse horário é melhor.
Para mim introduces an opinion here.
Na opinião da Luana, a sala precisa de mais luz.
Na tua língua de aprendizagem
English uses I think or I believe to present the speaker's view, and according to Nina to name another person's view or account. In my opinion and in my view clearly mark a personal judgment. A statement after think can begin with that, but that is often left out.
I think this chair is more comfortable.
I think marks this as the speaker's judgment.
In my opinion, we should start earlier.
According to Nina, this cafe has the best coffee.
The sentence presents Nina's view, not necessarily the speaker's.
Learners whose language uses a single person-marked word for an opinion may choose according to me when in my opinion would be more natural. Learners whose language requires a linking word before a reported thought may not realize that that can be omitted after I think.