老人吃饭和取暖不应吝惜。Older people should not skimp on food or heating.做糕饼时不要吝惜奶油.Don't scant the butter when you make a cake.老年人不应过分吝惜食物或取暖方面的开销.Older people shouldn't skimp on food or heating....
方法: 用溴代及胺化反应合成了四甲基吡嗪衍生物.METHODS: The target compound was prepared by the bromination and amination reaction.用溴—甲醇溶解Al_2O_3, 其回收率在91%以上.If Al 2 O 3 is dissolved by Br 2 - CH 3 OH, its Recovery rate is above 91 %.用溴比用氯时产出率...
这整个快要散架的搭建物吊挂在一棵枝繁叶茂的大树的枝杈上。This entire rickety structure was hanging from the limb of an enormous leafy tree.在它们的首端, 同时吊挂着一只画面朝下的 迷你 显示屏.At the upper end, I've hung a mini - screen facing downwards.你想让我把它放进那个吊挂箱里 吗...