I want a pen ＄4.A. to buy; for B. to buy; in C. buy ; in

问题补充：

I want a pen ＄4.

A. to buy; for B. to buy; in C. buy ; in

答案：

解析：句意：我想要花4美元买一支钢笔。want to do sth. 想要做某事。buy sth. for some money花费多少钱买某物。故选A。