Mesitylene carboxylic acid

mesitylene

n. [化]荚,1,3,5- 三甲基苯

carboxylic

[机] 羧基的

acid ['æsɪd]

adj. 酸味的;尖刻的;酸的;酸性的; n. <化>酸;酸味物质;

acid尖，酸，锐利 →酸；酸的，酸性的

The trouble is

问题是

How would you like to proceed with the negotiations?

你认为该怎样来进行这次谈判呢？

The only way that they can preserve their history is to recount it as sagas -- legends handed down from one generation of another.These legends are useful because they can tell us something about migrations of people who lived long ago, but none could wri

他们保存历史的唯一办法是将历史当作传说讲述，由讲述人一代接一代地将史实描述为传奇故事口传下来。