Words of encouragement create social capital as it makes the person who is being appreciated feel a sense of worth and make him or her a nicer, happier being.capital：表示资本吗？as 表原因吗？being是什么意思/用法？
The problem is that catalysts and membranes have been expensive until recently.请问这里catalysts and membranes是最近才开始变贵，还是从以前到最近一直都是这么贵，还是说以前一直贵，但最近不贵了？还请教 until recently 是否有多种不同的用法？
"The only thing she's mentioned is a ballerina dress. It's priced at $ 125. She's been invited to some parties by her friends at school."she's mentioned 是完成时吧？
...enthusiasm,conveys most strongly before formulas took shape and when there was more room for experimentation.我们都知道这里不能用conveys，要用其非谓语形式答案是conveying，理由是现在分词作伴随状语。我不这样认为，我认为答案应该是conveyed。百度出...
The bus was held up by the snowstorm,thus causing the delay.后面一个句子的主语和前一个句子的主语bus并不相同，可以转换为 The bus was held up by the snowstorm,so it caused the delay 为什么还可以省略
Only gradually was the by-product of the institution noted, and only more gradually still was this effect considered as a directive factor in the conduct of the institution.in the conduct of the institution 这里是 a directive factor的定语还是considered 的状语，为什么？
... clocks and watches that automatically adjust themselves over the Internet or by radio waves. These measurements allow them infinitesimal accuracy in dealing with time.最后一句是什么意思？是说这些方式处理时间非常不精准吗？