We began to open to the outside world in the ate 1970s. , there have been great changes in the country.

Mike take a bus to the office, but now he walking there.

Poor people don’t have money _______ medical treatment.

We study in a school ____ fame is known nationwide and it is a school _______ we can fully develop our potential(潜能)

Tom looked upon the test as an obstacle _____ his classmates regarded it as a challenge