1) I was surprised by the fact related to Ireland. It is surprising to me because I believed that life abroad was so expensive, so it would be hard to buy your own home. Since I believe it was hard, I imagined most people would depend on rented houses to live in.
2) I was surprised by the fact related to Canada, because there is a stereotypical image of men and women roles in my community where women do the housework and take care of children and where men are responsible for bringing in the money.
3) I didn't correct it because I don't exactly understand what you are saying.
4) Japan because I thought that industrial countries don't have strong family bonds, so I believed when the parents get older they would be taken to a nursing home.
In number 3 and 4 it is not really clear why you are answering the country (Japan because... Australia because...), I would write out an introduction in the sentence that is similar to the first and second entries.