It takes a long time to go there by train;it’s ________by road

The hill ____ is covered with trees is called Mang Hill. [ ]

China’s population is expected to increase to about 1.5 billion in 2040, ______it will start to decline slowly.

Li Ming often plays basketball to keep .

The English program normally attracts 1,000 students a year, ______ half will be from abroad.