I confess it. I am an English nerd. I admit that this is something I have known for some time, but I never realized it was quite like this. For instance, I actually enjoy teaching grammar. Of course, I have discovered that bad writing goes far beyond not knowing the difference betweeen past and present tense. I also know now that passive sentences are the mind killer.
While tutoring, I discovered this little editing trick. I wish it was par for the course in every high school English class. They call it the "Paramedic" method of editing sentences. Argh. As a tutor, I can't tell you how badly people are in need of this information. Here's how it works:
1a. Circle the Prepositions. Too many prepositions can drain all the action out of a sentence. Get rid of the prepositions, and find a strong active verb to make the sentence direct:
Original: In this passage is an example of the use of the rule of justice in argumentation.
Revised: This passage exemplifies argumentation using the rule of justice.
1b. Circle the "is" forms. Using "is" in a sentence gets it off to a slow start, and makes the sentence weak. Replace as many "to be" verbs with action verbs as you can, and change all passive voice ("is defended by") to an active voice ("defends").
Original: The point I wish to make is that fish sleep with their eyes open.
Revised: Fish sleep with their eyes open.
2. Ask, "Where's the action?" "Who's kicking who?" (using Lanham's own terminology here--to be precise, it would be "Who kicks whom?"). If you get stuck in a passive sentence always ask the question: "Who does what to whom?" If you use that formula you will always write active sentences.
Original: Burning books is considered censorship by some people.
Revised: Some people consider burning books censorship.
3. Put this "kicking" action in a simple active verb.
Original: The theory of relativity isn't demonstrated by this experiment.
Revised: This experiment does not demonstrate the theory of relativity.
4. Start fast--no slow windups. Stick to the action and avoid opening sentences with phrases like these:
My opinion is that....
The point I wish to make is that ...
The fact of the matter is that...
I discovered much of this for the first time in John Gardner's The Art of Fiction, which turned a decent book on writing into an eye-opening one. Much like you, I wondered how I could have come this far - and read so many other books on writing from so many other authors - before having this very simple idea pointed out.
Perhaps it's because the confusion of different tenses is one of the things that separates the good writing from the bad - but an awareness of things like passive sentences is something that can separate the good writing from the excellent.