Mr. Green has worked here ( ) he came to China. (for, since)
查看答案
His grandparents have been dead ( ) seven years. (for, since)
It's been five years ( ) we met last year. (for, since)
Mike and his parents ( ) the north for half a year.(have been to, have gone to, have been in , have been)
Mum is not at home now. She ( ) the shop. (have been to, have gone to, have been in , have been)