1. First clause doesn’t match second clause
Oh, no, not that seventh grade grammar language! I thought I left that behind in Mrs. Morell’s class! Well, yes, many people did. Here’s an example:
“When you use my services, they’ll really help you.”
What’s wrong with that sentence, other than the fact that it’s boring and colorless? The subject is “you.” The second part of the sentence must be about “you,” too. Example:
“When you use my services, you’ll find they transform your life.” Here, the “you” at the beginning matches the “you” at the end.
A more complex example: “By using integrated system techniques, the components build on each other.” Wait a minute. Who is using integrated techniques? Maybe you, maybe I, but definitely not “the components.” Say instead, “By using integrated system techniques, we make sure the components build on each other.”
2. Decorative apostrophes
An apostrophe indicates the possessive form. The cat’s paws. The priest’s robes. An apostrophe should never appear between a word and the pluralizing “s.” It’s NOT the cat’s whisker’s or the priest’s vestment’s.
3. What about it’s and its?
Ah, yes. It’s and its. They keep proofreaders in work so we’re not complaining. But here’s the secret: It’s means it is. That’s all it ever means. Its means belonging to it. So test out your sentence. If you can substitute it is for it’s, you’ve got it right. If not, you don’t.
4. Sally and I? Sally and me?
Which is it? Depends. Sally and I went to the workshop together. The workshop leader gave Sally and me some handouts. Got it? Here’s how to test the second sentence, the one that trips people up: When you take out “Sally and,” does the sentence still work? The workshop leader gave me some handouts? Yes. The workshop leader gave I some handouts? No.
5. Who or whom?
Don’t read this if you’re of the opinion that whom will be gone from the English language 50 years from now. On second thought, do read it. You want to be correct for the next 50 years, right?
Who wrote this? She did.
Whom should I ask? Ask him.
Who is speaking to me? She is.
To whom am I speaking? To him.
The clue to the correct question is in the answer. If the answer is he or she, put who in the question. If the answer is him or her, use whom. Without any fancy grammar talk about subjective case and objective case, that’s an easy test you can use. Just for the next 50 years, though.