Hello. I'll be very grateful if you will help me again.

Please tell me if the sentences are possible in normal English:
1)Iran remains unshakeable / inflexible / steadfast / unwavering in its position.
2)Iran's position stays / remains the same / unshakeable / inflexible.
3)Iran remains / stays in/on its position.
4)This position is grounded on the affirmation that its nuclear program is peaceful.
5)The prime minister is interested to learn / learn of/about / know / know about / get to know (about)/ study / get acquainted with the economic and social situation in Venezuela. (which article is correct: a / the situation?)
6)The conflict is an obstacle for the countries in signing an agreement.
7)Experts, on their part, consider the situation might change.
Thank you for your help. I really appreciate it.

1 - Any of these choices are fine.

2 - Any will work fine.

3 - I'd write, "Iran does not change from its position." But really -- 1 and 2 are better.

4 - OK

5 - I'd write, "The prime minister is interested in learning about the economic and social situations in Venezuela."

6 - OK

7 - OK