auxiliary

/ɑgˈzɪljəri/

functioning in a supporting capacity

Chinese meaning: 辅助的；备用的

The hospital has an auxiliary power supply in case of a blackout.

这家医院有备用电源，以防停电。

Auxiliary verbs help form different tenses in English grammar.

助动词帮助构成英语语法中的不同时态。