primary device的用法和樣例：
例句
- If the main device fails, the backup can take over, duplicating all the encryption parameters, that were in force.
如果主設備失靈，備用設備可切換過來，將所有有效的加密參數複製下來。 - The important significance of dynamic response analysis for primary components under accident conditions and the research status at home and abroad were reviewed.
回顧了主設備在事故工況下動態響應分析的重要意義以及國內外研究的現狀。
