Just some observations of mine. Disregard at your leisure:
“I was walking to school.” is not written in the passive voice. That verb tense is known as the “past continuous.” Most writing guides recommend that you change such “weak verbs” to the “simple past” tense; thus a better sentence will read: “I walked to school.”
The passive voice rears its ugly head when the subject is obfuscated or unclear. E.g. “The bed was made.” Who made the bed? Notice that both the passive voice and the past continuous forms use the verb “to be.” I believe this is the reason why many people confuse the two.
When is the past continuous okay to use? If one action happens while another is occurring. Example, “I was walking to school when a brick fell on my head.” In this case, the “to be” verb is necessary.
One of my pet peeves is seeing participial phrases used incorrectly (BTW, notice my weak verb). Participial phrases are those “-ing” constructions, such as, “I went to the store, sweating profusely.” The italics contain the participial phrase. Participial phrases (PP) like these that occur after a comma should always modify the subject of the sentence because they are in fact adjectives (otherwise known as adjectival phrases.) There are exceptions, e.g. “Bob saw Jack sweating profusely.” But if you have the comma: “Bob saw Jack, sweating profusely,” the “sweating” part modifies the subject, not the object.
Here’s an example of an incorrect usage (in my eyes) of a PP: “Jack went to the store, it being very crowded.” Notice the PP does not modify the subject, but modifies the object, “store.” Notice too that the PP attempts to add its own subject, “it,” which refers to the store. But then the verb, “being” is therefore in the wrong tense. If your friend asked you what the store was like, you would not say, “It being very crowded.” You would say, “It was very crowded.” Therefore, the correct sentence should read: “Jack went to the store. It was very crowded.”
Another example of bad PPs. “Jack lifted the ladder, Jane helping on the other end.” Again, the PP after a comma (in my eyes) should always modify the subject of the sentence. Otherwise, the PP sounds like a sentence fragment.
One more bad example: “I looked up at the tree, swaying in the breeze.” Who exactly is swaying here? Me or the tree? I think this makes my point clear.
Please note that I break this rule on occasion, as nothing is ever set in stone. I believe it is okay to break a rule if you are conscious of it. But in general, I try to apply these concepts to my own writing, and it irks me when I see people make these mistakes unconsciously.
Anyway, just ranting before I go back to work.