Ppbv
abbr. parts per billion by volume 十亿分体积比
🗣️ 情景例句
you're going to give me the answer to that question.
是要给我这个问题的答案。
New year's Eve comes one week after Christmas.
新年夜在圣诞节的一周后到来。
I like light green, but Lily prefers dark blue.
我喜欢淡绿色，而莉莉却更爱深蓝色。