一句英语语法填空

Question

Anyone who climbed up her tree ____ not be able to come back down until she permitted it.

空白处应填could 还是should 还是would为什么呢,请详细解答，谢谢

Answer 1

应该填“should”，原文是：
One evening, a passer by asked to stay for the night. Seeing that he had an honest Face, she let him in and gave him a nice treat. The next morning the stranger, actually a sorcerer (巫师), thanked her by granting (允准) her wish that anyone who climbed up her tree should not be able to come back down until she permitted it.

一天晚上，一个过路人请求要留下来过夜。看见他有一副诚实的面孔，她就让他进来，并盛宴招待他。第二天早上那位陌生人，确实是个巫师，多亏他许愿：任何一个能爬上树的人不经他允许不能下来

Answer 2

我觉得是would
因为根据题意，爬上她家树的人将不可以下来，除非她批准了

将不可以 就是will,虚拟语气就是would

Answer 3

应该填would.
could not是“不能”的意思
should not是“不应该”的意思
wound not是“不会”的意思，用于过去将来时

本句是说刚才爬上树的任何人，不经过她允许，都不能下来，句中已经用了be able to,所以不能用coule not,而且又是表示将来的动作，所以选would

Answer 4

would.