以单质碘为催化剂合成了环戊酮乙二缩酮.Cyclopentanone ethylene ketal was synthesized with I _ 2 as catalyst.传统的缩酮化、酯化反应工业上多采用浓硫酸作催化剂.Traditional ketalization and esterification reactions are usually catalyzed by concentrated acid in industr...
They would have to offer cast-iron guarantees to invest in long-term projects.他们需提供绝对可靠的担保，才能投资长期项目。Business is booming and foreigners are scrambling to invest.商业繁荣，外国人争相投资。She wanted to set up her own company to invest ...
“ 天哪! ” 和 “ 哎哟 ” 都是感叹词." Good Heavens! " and " Ouch ! " are interjections.俄语感叹词是表达情感和意愿的词.Russian exclamations are words that express feeling and willingness.是形容词 吗 ?是感叹词 吗 ?还是夸大其词?Are they terms of endearment ? epithets...
Certainly. The fitting room is over there.当然可以. 试衣间在那儿.M: May I try this on? where is the fitting room?猴子: 我能试穿一下 吗 ?试衣间在哪儿 啊 ?You can try on the dress in the fitting room.你可以在试衣间试穿这件连衣裙....