There are many ways to give your opinions when speaking English. The exact English expression you use depends on how strong your opinion is.
I think; I feel; I reckon (informal)
I guess (American)
In my view/opinion (formal)
Apparently; so to speak; more or less; sort of (informal)
Kind of (informal)
Well; really; that is to say; at least; I am afraid; I suppose; or rather; actually; I mean
Giving your opinion neutrally
I think/ feel/ reckon/ guess and in my view/ opinion are used to make opinions and statements sound less dogmatic.
•I think she is lying.
•I really feel she is making a mistake.
•I reckon/ guess she just doesn’t love him.
•In my view/opinion, it would be better to call the police.
Apparently can be used to say that the speaker has got his/her information from somebody else (and perhaps does not guarantee that it is true).
•Have you heard? Apparently Alice is pregnant again.
So to speak, more or less, at least and sort/kind of are used to show that one is not speaking very exactly, or to soften something which might upset other people. Well and really can also be used to soften.
•I sort of think we ought to leave now.
•I kind of think we are going to lose.
•She is kind of strange.
• ‘Do you like it?’ ‘Well, yes, it is all right.’
•Ghosts don’t exist. At least, I have never seen one.
I am afraid
I am afraid (that) often means I am sorry to tell you (that). It is used to introduce apologetic refusals and bad news.
•I am afraid I can’t help you.
•I am afraid I forgot to post the letters.
I suppose is used to enquire politely about something. It can also be used to suggest unwilling agreement.
• ‘I suppose you are very busy at the moment?’
• ‘Can you lend me some money?’ ‘I suppose so.’
Or rather / I mean
Or rather and I mean can be used to correct oneself.
•I am seeing him in May – or rather early June.
•Let’s meet next Monday – I mean Tuesday.
We do not usually give our own opinions with according to.
•In my opinion, she is sick. (NOT According to me, …)
Giving a strong opinion
•’I’m absolutely convinced that…’
•‘I’m sure that…’
•‘I strongly believe that…’
•‘I have no doubt that…’
English expressions for asking someone’s opinion
•What do you think?
•‘What’s your view?’
•‘How do you see the situation?’