Which is right, ‘by contrast’ or ‘in contrast’?

The common phrases “in contrast” and “by contrast" are often changed by editors when these phrases start a sentence as an introductory phrase in formal English. Which one is right?

Which is correct, “though” or “although”?

According to several sources like the Cambridge Dictionary, "although" and "though" have the same meaning. However, “although” is considered to be slightly more formal in style. Google Ngram Viewer tells us that “though” is increasingly more commonly used, but “although” is holding its own. Of course, the Ngram Viewer does not tell us how those words are…