下午好！我的房号是321。

Good afternoon, my room number is 321.

法航321班机是去罗马的直达班机。

AF flight 321 is a direct flight to Rome.

法航321班机是去罗马的直达班机.

AF Flight 321 is a direct flight to Rome.

柯达321A型微胶片阅读器操作简便，功能齐全，结构紧凑，造型美观。

The KODAK Fiche reader 321A is easy to operate, versatile. , compact and has a pleasing modern design.

这321英里长（ 517公里长）的水体是唯一的大湖完全位于美国之内。

This 321-mile-long (517-kilometer-long) body of water is the only Great Lake located entirely within the United States.

低压电涌保护装置用元件.第321部分: 雪崩二极管的规范 ( ABD ).

Components for low - voltage surge protective devices - Part 321: specifications for avalanche breackdown diode ( ABD ).

柯达（KODAK 321A）微缩胶卷阅读机，易操作、功能全、小巧灵活、现代新型设计。

The KODAK Fiche reader 321A is easy to operate, versatile, compact and has a pleasing modern design.