variable - frequency timing的用法和樣例：
例句
- The maturing of variable frequency technology becomes an assurance for the reliable operation of a trolley type scraper.
變頻調速技術的成熟是滑線式鏟運機可靠工作的保證。 - Potpourri control of the microcontroller Frequency Control System is used to thinking poor frequency control.
單片機控制的變頻調速系統設計思想是用轉差頻率進行控制。
