auxiliary

The hospital relies on an auxiliary power generator to keep life-support machines running during blackouts.

(Chinese) 医院依靠备用发电机在停电期间维持生命支持系统的运行。

The large ship used an auxiliary engine to navigate through the narrow harbor entrance.

(Chinese) 这艘大船使用辅助发动机穿过狭窄的海港入口。

In the question 'Do you like apples?', the word 'Do' acts as an auxiliary to form the interrogative.

(Chinese) 在“Do you like apples?”这个疑问句中，“Do”作为助动词构成疑问句。

English learners often struggle with using the correct auxiliary in the perfect tense.

(Chinese) 英语学习者经常在完成时中使用正确的助动词方面遇到困难。