Picture a ruler cut into three steps, and this word placing something on the third step. That is all the word itself says: third step of somebody's scale. It does not say whether step three is the worst or the mildest — the person who built the scale decided that. Burn doctors built theirs by depth, so step three is the deepest. American courts built theirs by seriousness, and they count , so step three is the lightest.
可以想成一把被切成三格的尺，而這個詞做的事只有一件：把東西放進第三格。字本身不告訴你第三格是最重還是最輕。那是訂尺的人決定的。燒傷科的尺按「有多深」來排，所以第三格最深、最嚴重。美國法院的尺按「有多重」來排，而且是往下數的，所以第三格是三級裡最輕的。同一個詞、同一個位置，方向卻相反——看後面接什麼字，就知道現在用的是哪一把尺。