Say the same differently.Use the new words

1) John learns a lot OR is doing his homework.2) relationship of these 2 countries is good3) Biology studies organisms and their vital activity, nature in general and their relationship between them4) working on PC — is the most "popular" job of many people.5) it makes us think, when we see people harming the environment, or just doing bad stuff.6) Mr.Robinson thought that putting a high wall around the castle is a good idea.7) why is it necessary to eat useful food for children? 8) How many people live in LOndon? 9) Julia collects books OR Julia has library with lots of books at home.10) could you answer some of my questions?