题目内容：

To his disappointment,his suggestion that the lab ___ to students every day was turned down.
选择should open a还是should be open

优质解答

should be open

追问：

为什么不用should open 它做动词讲不也是可以吗

追答：

因为此处为被动语态，表示状态，be open to对.....开放