secondary filter的用法和樣例：
例句
- The flow field around the secondary filter was vividly characterized with a porous medium model, so that the flow pattern around this kind of filter was readily obtained.
多孔介質(zhì)模型形象地描繪出了二次濾網(wǎng)的內部流場(chǎng)，獲得了該型號濾網(wǎng)的內部流動(dòng)規律。 - By replacing your air filter annually, or biannually if you live in a dusty area, you'll ensure the engine can breathe freely.
每年換一次過(guò)濾器或者在沙塵多的地方每半年更換一次能保證你的愛(ài)車(chē)引擎自由呼吸。
