I have bought a chicken ,some beef and some vegetables in case your friend _to lunch

问题描述:

I have bought a chicken ,some beef and some vegetables in case your friend _to lunch
A should stay
B should have stayed
C have stayed
D stay
为什么选A

should 作情态动词时,有“会”的意思.
题意:我买了一些鸡肉,一些牛肉和蔬菜万一你朋友会留下来吃午饭.