She went to American two years ago .She ____there for half a year and then went to Japan.
He has three brothers, ________ is a doctor.
He never reads anything _______ is not worth reading.
―When was the house built? ―It was built in 1949 _______ the PRC was founded.
________ is known to everybody, the moon travels round the earth once every month.
This is Mr.Smith, ________ I think has something interesting to tell you.