With strange, archaic rules, as well as numerous exceptions to those rules, English grammar is just plain tricky. It makes sense that people tend to ignore the more obscure ones and focus on the day-to-day rules that make regular communication easier. However, when you’re writing to impress, it always helps to use some more sophisticated sentence structures.
Compound Subjects and Verbs
A compound subject can combine two elements with "and" (Jim and Pam) or with "or" or "nor" (Jim or Dwight). The verb is simple enough with "and." "Jim and Pam went to work." Since "Jim and Pam" is a plural compound subject, the verb (went) is plural as well.
But when the compound subject is separated by "or" or "nor," the verb tense will agree with the most recent noun.
"Jim or Dwight answers the phone." (Singular verb tense)
"Neither Toby nor the rest of the office want to go to lunch with Michael." (Plural verb tense)
We’re going back in time here. "You" was the polite version of "thou," and not the other way around. Even though it may sound stuffy now, "thou" was considered informal and used when a speaker had a degree of familiarity with the other person (like “tu” and “usted” in Spanish). To use "thou" with someone who was considered higher status, like a king, was disrespectful.
Em-Dashes and Hyphens
Em-dashes, hyphens, and en-dashes are not interchangeable. (Em-dash: — En-dash: – Hyphen: -)
Em-dashes are used as heightened parentheses. If you want to insert a thought into your sentence, em-dashes will work best. For example, “I thought we were friends — more than friends, even!”
En-dashes are used to separate values. For example: “I drink about 3-4 bottles of water a day” Hyphens are reserved for compound modifiers. For example, “I love my blue-green convertible."
A and An
The articles "a" and "an" are used based on vowel sounds, not the actual vowels used. The phrase “an hour” is grammatically correct while “a hour” is not.
The subjunctive tense in general is confusing, and not something you think about unless you're in a grammar class. But it's one of those things that can really elevate your speech. It specifically describes something that is not a known objective fact, such as a mood, a wish, or a dream. For example, “If I were to win the lottery, I would never have to work again.”