Question

Have not you seen the notice"No photos___"? I am sorry ,i ___.

A is allowed taking , did not notice B is allowed to take , was not noticing
答案是B，谁能说明为什么

Answer 1

B
首先,is allowed to do sth 是正确用法
其次,一般会觉得was not noticing 别扭,但这是强调在刚才那个时间没有注意到,是对过去的动作的描述,所以用过去进行时态.

Answer 2

B
一定是be allowed to do被允许做某事。did not notice 和was not noticing 都可以。

Answer 3

1. allow to do sth 被动就是be allowed to do
2. 我刚才没注意到（言外之意，现在注意到了），刚才没注意，是一瞬间的事情。所以用ing

Answer 4

B is allowed to do sth 是正确用法

Answer 5

感觉都不大对