After visiting China,most of the foreign friends said they would never forget the time ________ they had spent in China.
The modern history of Italy dates from 1860, ______ the country became united.
We will be shown around the city: schools, museums, and some other places, _______ other visitors seldom go.
The old building, behind _______ was a famous church, was _______ we used to work.
The little time we have together we’ll try _____ wisely.
We are living in an age ______ many things are done on computer.