oughtn't
ought not 的缩写
例句
He oughtn't to have been driving so fast.
他本不该把车开得那么快。
《牛津词典》
Oughtn't the water to have boiled by now?
水现在该开了吧？
We're his friends--oughtn't we to do something?
我们是他的朋友——难道我们不应该做点什么吗？
