题干
—Why don't you use your own knife?
—Sorry, I've _____ it at home.
A：lost
B：forgotten
C：kept
D：left
答案(点此获取答案解析）
D
—Why don't you use your own knife?
—Sorry, I've _____ it at home.
A：lost
B：forgotten
C：kept
D：left
，输出相应的点
．若
的坐标为
，则
间的距离为