我国是以专利申请日为判断一项发明是否为现有技术的时间标准，申请日以前（包括申请日当天）公开的技术属于现有技术。
参考答案：错
请和Nick一起正确使用近期所学词汇来完成短文，表格内容和已给出的首字母可能对你们有用。
boy girl 12 13 big strong tall thin slim helpful English American Chinese
James √ √ √ √
Kate √ √ √ √ √
Chris √ √ √ √ √
Hi! I'm Sammi. My family are in Beijing now. I'm in No. 10 Secondary School. I have t 1 new f 2 in
my new school. They are James, Kate and Chris. James is English. He is t 3 years old. He is t 4 . He is my
classmate. Kate is American. She is a nice girl. She is t 5 and s 6 . She is thirteen years old. Chris is b 7
and s 8 . He is Chinese. He is thirteen years old t 9 . They are all h 10 .
中心导体法，对于大直径和管壁很厚的工件，管外表面的灵敏度比内表面有所下降
