When his mother came in, Charlie pretended _________.
When a disaster occurs, all people, ________ they are old or young, rich or poor, try their best to help those in need.
A trend_______ that 3D films will become more popular ever since the film Avatar hit the market.
The time is not far away ________ modern communications will become widespread in China’s vast countryside.
He managed to reach the summit of his career, but it was at the ________ of his health.
China was cracking down on drunk driving, including fines, 15-day detention, and having licenses ________ for up to 6 months.