What can I buy _____my mother's birthday?（填上介词）

I’m not sure what I can buy for my sister.（改为同义句）I’m not sure _____ _____ _____ for my sister. What should I _____(buy)_____(give)them -_____ -I'd like to buy a new coat.A.What do you want?B.What can I do for you?C.How do you like it? I can buy some snacks改为一般疑问句_____ _____buy_____snacks _____?--I want to buy some fruit.A.Can I help yo_____?--I want to buy some fruit.A.Can I help you B.What do you want to do Andy likes meat.I can buy _____ some chicken.Kate likes fruits.I can buy _____ some mangoes. 改为同义句：I don’t know what I should buy her.I don't know _____ _____ buy her. What can I buy with 100 Chinese yuan in Shenyang? I can't decide _____.Ato buy which one Bwhich one to buyC to buy whichDwhich to buy one can i buy your I can't decide _________.A what to buy B which to buy I will do what I can _____ you with Chinese. 同义句you can come here and buy what you want _____ ______? I have no _____(much) money.I can't buy anything.为什么填more I want to buy a new T--shirt,but I don’t know _____.A.which one to choose B.what to choose it C how to choose them D.where can I choose it --What can I do for you?-I'd ___ ___ buy a pair of sport shoes. I don't know what I can buy for her .如何改为同义句 what can I _____ for breakfast A.eat B.have