题干
People are often at a loss when frequently seeing smog level predictions ________ each other in different official forecasts.
A：contradict
B：acknowledge
C：allocate
D：circulate
答案(点此获取答案解析）
A
、
、
、
的四张卡片中抽出两张卡片，使其能合并同类项，则抽出的卡片分别标有 、 ．