题目

David has        China for five years. A. been to                B. come to  C. arrived in              D. been in     答案：D. 根据题意“戴维在中国待了五年了”可知 应该用has been in。故选D。若双曲线-=1的左焦点在抛物线y2=2px的准线上，则p的值为    ．