Unfortunately, as a standard mattress wears, the springs soften and so do not support your spine...遗憾的是，当一张标准床垫用旧后，弹簧就会变软而无法支撑你的脊椎。The bed-springs creaked.床垫的弹簧嘎吱作响。Ferroalloy and Products, Springs and Coils, Cold, Hot, ...
这次提升标志着她事业上的转折点。The promotion marked a turning point in her career.19世纪中叶标志着俄国历史的转折点。The middle decades of the 19th century marked a watershed in Russia's history.他就任教师工作是他一生的转折点.His induction as a teacher was a tur...
环己酮和过氧化物可用来化替过氧化环己酮.Cyclohexanone and peroxide may be used in place of cyclohexanone peroxide.己酮糖:一种六碳的酮糖.例如果糖.Ketohexose A ketose SUGAR with six carbon atoms , e . g . fructose.提出了环己酮在这类催化剂上双聚反应的机理.Reaction pathway of c...