Uspto
abbr. U. S. Patent and Trademark Office 美国专利和商标办公室; United States Patent and Trademark Office 美国专利和商标局
🗣️ 情景例句
The rural workforce has been flowing in to the cities ever since the open door policy was adopted.
自从改革开放政策实施以来，农付劳动力正不断流向城市。
Better be alone than in bad company.
交损友不如无友。
What's it used for?
有什么用途？