China's high-speed railways _________ from 9,000 to 25,000 kilometers in the past few years.
are growing
have grown
will grow
had grown
________of the people on the Net ________China's economy is among the strongest in the world.
Nobody but doctors or nurses and those ________ by Dr. Hu ________ to enter the patient's room.
The population of China ________ 1.3 billion,and 80% of the population________farmers.
Every possible means ________ to prevent the air pollution,but the sky is still not very clear.
It is reported that 40 percent of the land in Brazil________covered with trees.