A couple of random thoughts that have been running through my mind lately.
The word "never". By definition it means: not ever, at no time, not at all, absolutely not, to no extent or degree. I've noticed several authors using never to mean "did not." It's a common way of speaking in some parts of the country, but it isn't always proper English.
Consider the sentence: "He never saw his assailant." That statement is only true if he has never seen the assailant in the past and won't see him in the future. It's a hit and run or the character dies from the blow from the assailant.
But, I've seen that sentence in this situation. "He never saw his assailant. The blow to the head knocked Sam unconscious. When he woke up, his hands were tied and he saw the assailant watching him through hooded eyes." ...ummm wait a minute. I thought Sam never saw the assailant? It should read "He didn't see his assailant" for the paragraph to make sense.
That's nitpicky, but the word never is one of those words that writers tend to latch on and overuse.
I think the reason that I notice this is because I've spent the past year editing Mette's Annals of Hypnosia. She's Finnish and very fluent in English, but occassionally she writes a phrase that is a bit off. It's my job to catch those things. Usually it is a preposition that is the culprit. Technically, one could say the phrase the way she wrote it, but a different preposition would be used by a native speaker of English. Which led me to the thought that an easy way to convey that English isn't the character's first language is to misuse prepositions in their speech.
I have to say that I am in awe of anyone who can write in a second or third language and have it not be that noticeable to a native unless they are looking for it.