One of the amazing things about language is that it lets you express thoughts that have never been expressed before and describe situations that may never have been imagined.
Even so, in any language there are some kinds of thoughts, and not necessarily new or unusual ones, that the grammar rules don't give you an easy way to state. If you think of your language as a vast and sprawling place, then your grammar is the network of roads that allows you to get to where you want to go. And these troublesome thoughts are areas that are just beyond where the sidewalk ends, just past the Dead End sign in a subdivision. To express them, you can take a detour and use circuitous but established routes to get there — or you can go off-road, making a more direct path to the destination, using rules of grammar that don't quite exist yet.
Here are a few examples of off-road grammar in English.
Gradable adjectives and noncount or plural nouns
You can say that Mr. Fenwick is "too strict a teacher" to give extra credit, or that Harry Potter and the Deathly Hallows is "as good a book" as Fifty Shades of Grey. You might ask "how long a drive" it is between your friend's house and her new job. (Some might say "too strict of a teacher," "as good of a book," or "how long of a drive," but that's a topic for another day.) It's a little unusual to have the adjective phrase too strict, as good, or how long before the word a, when the usual syntax would put the adjective after it: a strict teacher, a good book, a long drive. Still, speakers are comfortable doing it, whether their dialect uses an of or not.
But put in a noncount noun or a plural noun, and all of a sudden you're off-road. Do you say that some place has "too cold weather" or "too cold of weather"? Did your child have "too low grades" to make the honor roll? "Too low a grades"? "Too low of grades"? Would you ask "how hot a coffee" a diner served, or "how hot coffee"?
If you take your best guess, you choose one of those options, ignore the momentary disorientation, and move on. If you take a detour, you might refer to "weather that's too cold," or say that a kid's grades "were too low to make the honor roll," or ask "How hot is the coffee?"
Reciprocal pronouns in embedded clauses
Two people can like each other, talk to each other, or give each other presents. But if we go beyond simple clauses like those to clauses that contain clauses, it's not so easy to use each other. Suppose Kim thinks Sandy is awesome, and Sandy thinks Kim is awesome. Do you say, "Kim and Sandy think each other is awesome"? "Kim and Sandy think each other are awesome"? Awkward. Or if Kim thinks someone should talk to Sandy, and Sandy thinks someone should talk to Kim, how do you say that? "Kim and Sandy think someone should talk to each other"? That's not just awkward; it's ungrammatical, because the each other now wants someone to be its antecedent instead of Kim and Sandy, and that makes no sense.
The detour for these situations is to go back to an earlier stage in the development of each other, before they were practically one word: Kim and Sandy each think the other is awesome. Kim and Sandy each think someone should talk to the other.
Suppose you return to your parking spot to find that your car is gone. You might say, "Somebody stole my car!" Alternatively, you might say, "My car has been stolen!" They're both good sentences; it's just a matter of whether you want to mention the stealing first, or your car first.
Now suppose that we're talking about a Mafia informant who has just been lucky enough to be somewhere else when his house was bombed. You could say, "Somebody attempted to kill the witness." But what if you want to mention the informant first? Unfortunately, you've reached the end of the road; English grammar doesn't provide a clear way to do this. "The witness attempted to be killed"? No; that sounds like the witness put the hit on himself. "The witness was attempted to kill"? No, that's just plain ungrammatical. The off-road option that sometimes gets used is to put both attempt and kill in the passive voice: "The witness was attempted to be killed".
This kind of "double passivization" also happens with other verbs that take an infinitive, such as remember, forget, continue, and manage. Grammar writers who notice it criticize it. The detour is just to use the active voice, and say that "someone" remembered, forgot, continued, or managed to kill the witness.
So the next time you're wondering which of several possibilities is the grammatical way of saying something, the answer might be that none of them are... yet. But if you're not in the mood for the scenic route, be bold and go off-road. The path you choose may be the one that ends up graded and paved as the newest addition to English grammar.