Once you get your first draft onto the page, it's time to clean up the words and make sure that you're conveying the proper meaning. The following points are things you should consider while you're editing.
Many beginning writers fall into the trap of believing that their words are sacred. If you want to become an effective writer, then get used to the idea that everything is subject to change.
Subject and Verb Agreement
The verbs you use must always agree with the subject to which they correspond. For example:
He goes to the store every Tuesday.
They go to the store every Tuesday.
Note how the form of the verb changes to match the pronoun. Of course, not all of your subjects will be pronouns. Often, you will start sentences using regular or proper nouns:
Sam goes to the store every Tuesday.
Sam and Bill go to the store every Tuesday.
Two singular subjects, when acting together, will take a plural verb. Make sure that your sentence construction uses the proper agreements.
Verb Tense Agreement
There are three basic tenses in the English language: the past, the present, and the future. In most writing, you will use the past tense, especially when you are describing events that have already occurred.
The past tense has further divisions, too. You can talk about events that occurred in the past, and you can also talk about events that occurred before those events. You have to be careful to make sure that you are using these tenses properly, or mass confusion could result. Even if confusion doesn't arise, improperly constructed sentences can still look silly; this also makes the reader wonder if the author knows what he or she is talking about, so if you're not careful, you could risk losing credibility in your writing.
Verb tense agreement can be hard to get used to at first, but it's really not that difficult. Consider the following example:
Mandy walked into the bathroom, picked up the towel, and began to dry her hair. When she was done, she put the towel back where it was.
Wasn't the towel just in her hair? Where, exactly, would Mandy be putting the towel, then? In the first sentence, all of the verbs are in the immediate past tense. In the second sentence, the verbs are still in the immediate past. When it comes to where the towel was, however, the verb is referring to where the towel was before the other events took place. Therefore, a slightly different tense is needed:
Mandy walked into the bathroom, picked up the towel, and began to dry her hair. When she was done, she put the towel back where it had been.
Now the verbs clearly show that Mandy put the towel back in the place it had been before she picked it up. When compared to the other example, it is much clearer (not to mention grammatically correct). Pay careful attention to your verb tenses to make sure that your writing refers to the correct time period.
Some people just fall into the habit of making their sentences run on too long, so that you end up with really long sentences, and with other clauses tacked onto the end without any bit of a break, making up one of the longest sentences you could ever hope to find, no matter how hard you look, and you end up going on forever before you ever come across a period, and even then it seems almost like an afterthought.
See, then, how bad a run-on sentence can be? As a general rule of thumb, a sentence should only have one point. Sometimes you can add on another point as a sub-clause, but if it gets any more complicated than that you should consider breaking it up into much smaller bits.
You should always try to vary the length of your sentences. Intersperse them. Don't use a lot of short sentences unless you're trying to establish a scenic objective, such as suspense. Or immediacy. You're much better off staggering the sentences so that you have longer ones broken up by shorter ones. This creates variety and keeps things interesting for the reader.
No matter what you write, you should always keep your readership level in mind. If you're writing for a group of children, you'll want to use simple concepts and simple language to convey your meaning. Historical references must often be explained for them to have meaning and establish the context you intend. If you're writing for a group of academics, your language will be aimed differently. But unless you have an idea of who your readership will be, you should err on the side of caution and assume a readership level of about seventh to tenth grade.
Some dictionaries contain listings that show “spelling” words for each grade level. However, academic standards change. Check with your local school office for suggestions on where you can obtain such grade-level lists and use them to compare the words used in your writing against those suggested for your intended audience. If you're already working with a children's book publisher, check with your editor or consult the publisher's writing guidelines for suggestions.
A good rule of thumb is just to keep all of your writing as simple as possible. That way, it can be understood by a reader of almost any level. You may not want to write for a grade-school level, but aiming for a high-school crowd is completely acceptable in most circles. Of course, sometimes a higher level of diction is called for, such as with an academic crowd. The trick is to figure out who your audience is and then aim appropriately.
One of the magic things about the English language is that there are so many ways to say things. You can convey information in a very formal manner, or in a number of degrees of informal ones.