According to the school rules, a student ______ report any damage to school properties to a teacher or the office immediately.
Eye doctors recommend that a child's first eye exam ________ at the age of six months old.
Had they known what was coming next, they ________ second thoughts.
Grace doesn't want to move to New York because she thinks if she ________ there, she wouldn't be able to see her parents very often.
If he had spent more time practising speaking English before, he ________ able to speak it much better now.
If we ________ a table earlier, we wouldn't be standing here in a queue.