Kong Xiangdong became a great pianist in ___1980s when he was only in _____teens .
_______, he went upstairs to sleep without supper.
______ you may have, you should gather your courage to face the challenge.
That’s the factory _______we paid a visit last year.
The field research will take Joan and Paul about five months; it will be a long time _____ we meet them again.
All the travelers _____that they should bring their ID cards with them.