I want to buy( ).A a trousers B a pair trousers C a trousers D a pair of trousers选哪个?为什么?

I want to buy a house _______money. I want to buy a present______mu cousin I want to buy a hair c____ I+want+to+buy+a+postcard. I want to buy a _______of shorts. I want to buy a p____of shose want,ruler,buy,I,a,to I want to buy a pair of_shoes I want to buy a paiI want to buy a pair of_shoesI want to buy a pair of_shoes i have a coat ,i want to buy a b I want to buy a gift I want buy a gift 哪个对?为什么 I want ( )a pen ( )$4.A buy for B to buy for C buy from D to buy from want to buy a new 改错I want to buy she a present． i have enough money and want to buy a car I want to buy a large box of chalks.改错 I want to buy a pair of shoe.咋改? I want to buy a pair of shoes=? I want to buy a car of _____own.