.. All books ___________ to the library more than three days late will be subject to a fine.
The girl often helps her best friend, ______ is not good at English. To their delight, his English is improving day by day.
When Li Lei was a small child, he hoped to be ______ policeman after he grew up and finally his dream came true.
The construction of the gym caused much noise, it difficult for people nearby to sleep.
She won’t be able to come next week, because she_________herself in Mount Tai then.
When a student asks__________it is worth staying up doing their lessons, a teacher may find it difficult to answer.