Indispensible
不可或缺
🗣️ 情景例句
After I finish my homeword, I usually watch TV for half an hour or so.
我做完作业后，通常看半个小时的电视。
Who is he?
他是谁？
you will realize that a modern navy is a good place to study noise.
你就会认识到现代海军是研究噪音的好地方。