對汽車而言，一般建議每跑1萬至1.5萬公里就換一次油，這樣引擎才能一直保持順暢運轉。 如果你經常在城市開車，可能得更勤換油。 至於機車機油多久換一次，就看你的騎乘習慣和車型了，但一般每5,000至8,000公里換一次是明智之舉，有助於引擎保持最佳狀態。

For cars, it is generally recommended to change the oil every 10,000 to 15,000 kilometers so that the engine can keep running smoothly. If you drive a lot in the city, you may need to change your oil more frequently. As for how often motorcycle oil should be changed, it depends on your riding habits and model, but it is generally wise to change it every 5,000 to 8,000 kilometers to help keep the engine in optimal condition.