usable floor area的用法和樣例：
例句
- The gro area is around four hundred and fifty square feet and the net area is three hundred square feet.
建築面積約四百五十平方英尺，使用面積約三百平方英尺。 - The application program area is employed by the system programmer for implementing the control program.
這個應用程序使用面積是由系統程序員實現控制程序。 - I use the floor cleaner to remove grease.
我用地板除垢劑清除油污。
