Some chunks of language are more useful than the others, in the same way as chunks (expressions, constructions) are more useful than isolated words for communication. At the end of the day after ability of asking and answering basic questions, next thing in terms of usage frequency is ability to give an opinion. Don’t get me wrong – I don’t urge you to run around and doing hard sell of your opinions. But if you think about the way we communicate then you realize that apart from basic Q&A we do a lot of this “opinion giving” either to share our opinion with others on our own accord or upon request, and we do this both in formal and informal communication. I think you would agree that we should not underestimate expressions for giving opinion and it is very useful to know them early in your language learning journey.
Here is a list of expressions you may use for giving your opinion in French.
In my opinion – à mon avis / Selon moi / D’apres moi / Pour moi etc.
As for me – Quant à moi
For my part – Pour ma part / Pour ma part je pense que…
I’m not sure that… – Je ne suis pas sûr que…
I think that – Je pense que / Je crois que / Je trouve que
As far as I’m concerned – En ce qui me concerne
It is obvious that… – C’est évident que…
What strikes me the most is… – C’est qui me frappe le plus c’est…
I maintain that – Je soutiens que
I have feeling that – J’ai le sentiment que
It is without doubt – C’est sans aucun doute
I took all these expressions from the video by Pascal whose channel on YouTube I may recommend to all learners of French. And you may also watch it to get an idea about how to pronounce all these expressions.