Mr Green has worked in China since Hong Kong returnde to China .since后划线部分提问

Question

———Mr Green  _in China I have never been to the sea side before 同义句I _ _ _to the seaside  before  昨晚我们总共十二人吃晚饭there were twelve of us_______fore dinner last night

Answer 1

how long has,worked .;have not been; to have

Answer 2

since 的意思是从过去某个时间起一直到现在为止，所以主句的时态用现在完成时，这个句子是since HongKong returened to China, 值的是从香港回归祖国的那一天一直到现在，我的父亲都在中国工作，所以前边用has been worked