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

It _____ last week that the haze(雾霾)in Beijing caused many problems.

One advantage of owing your own car is ________ you can go anywhere at any time you like.

Long time no see, Jim! You look much _.– Yes, people always change a lot.

In the city the old _______