Ancova
abbr. 協方差分析（analysis of covariance）
??? 情景例句
Snow.
雪。
Why are you so mean? I've never done anything to you.
兇什么兇？ 我又沒得罪你。
because balloons can be a great danger to aircraft.
因為氣球有可能給飛機造成極大的危險。