What does the letter “o” in the word “mother” pronounce发音

I shall never forget those years ________I lived in the country with farmers， ________has a great effect on my life.

1I am very sad that I ______many chances in the last few years.

I ______ through that bitter period without your generous help.

Can you show me _______ to use this kind of camera-Sorry, I don’t know, _______.