【单选题】白砂糖和赤砂糖的价格不一样,这是运用了()的定价法。
【简答题】—Many flights were _____ because of the bad weather . —What a pity!A. taken off B. fallen off C. turned off D. called off
【简答题】混凝土采用蒸汽养护后,其早期和后期强度均得到提高。
【判断题】混凝土采用蒸汽养护后,其早期和后期强度均得到提高。( )
【单选题】—Many flights were _____ because of the bad weather . —What a pity!