Og 83, 为什么要用will

83. Any medical test will sometimes fail to detect a condition when it is present and indicate that there is one when it is not.

(A)  a condition when it is present and indicate that there is one

(B)  when a condition is present and indicate that there is one

(C)  a condition when it is present and indicate that it is present

(D)  when a condition is present and indicate its presence

(E)  the presence of a condition when it is there and indicate its presence

答案没有问题，为什么Any medical test will sometimes fail 用will？

以下是引用薰衣紫草在2005-6-16 6:35:00的发言：
used like 'can' to show what is possible:

This car will hold five people comfortably.

姐姐好厉害的！这么细微的知识点都了