数量不稳定英语

According to the mail of Tim, the delivery date of the big motors is as follows. Since this is a new product, the production capacity is still not stable, so the quantity from the supplier may not reach our requirement. As the components of the small motors are still under modification, the specific delivery date is not fixed yet.

instableunsteady

一般的区别是,fall是强调自己掉下,而drop是强调被人掉下. 但如果说数据下降了多少,两个都可以. 其实如果留意一下英语新闻,还可以用别的词,例如说“股价下跌了10%”,可以说The share price fell/dropped/tumbled by 10% （或者shedded 10%）

unsteady/unstable