French language Q&A Forum

Hello, what is the difference between the usage of these two words please? Or are they interchangeable? Merci d’avance! 

...“et de lui acheter”. It seems to function like “et en lui acheter”, but for some reason “de” is the correct choice here. 

Mon voyage autour du monde a été une aventure merveilleuse.

Isn't it an opinion? Description? 

This question was found on a C1 test.  The answer that was provided was:  Nous avons ouvert les fenêtres de peur qu'il n'ait une fuite de gaz.

My problem is with the use of the word might.  Might means may be, could be, which suggests the use of pouvoir, de peur qu'il ne puisse y avoir une fuite de gaz.  When translating the answer that was given, I would say:  We opened the windows out of fear there was a gas leak.  No might is needed.

I thought that "Y" cannot be used with regard to people. But  have just been given a correct answer as Il pense à sa famille. Elle y pense aussi. Is family not a unit of people?

Is it OK to use fréquemment instead of souvent?