下面四个英语句子有两个各有一处错误，请帮我找出来并改正。

Question

Rooms will be cleared in the late morning.
Visitors will allowed to stay in the building after 9pm.
Doctors will be waited 24 hours a day.
All competitors will be expected to behave politely to each other.

Answer 1

1，将wil be改成was。
2，将allowed改成allow。
3，将will be 改成 were。
4，将be expected to 改成remain