He was too tired and fell asleep with a book open on his knee.
The house, ____________is blue, will be used as a library.
Petroleum(石油), along with fuel gas, ________ in price. Thus a larger amount of money __________ spent on transportation.
---You are late again! We _________you could attend the assembly on time. ---Sorry, I __________to my office to get my papers.
It’ s suggested by experts that teenagers ____at least 30 minutes exercising, five times a week.
The use students ________of the chance to travel and see new things really _______.