《词汇大师》今天讨论的是四种常见句子错误，准备好了吗，擦亮眼睛，一起来纠错！

Broadcast on COAST TO COAST: July 8, 2004

AA: I'm Avi Arditti. Rosanne Skirble is away. But with me from Los Angeles this week on Wordmaster is English teacher Lida Baker.

LB: "What we're going to talk about today is four types of common sentence errors, the kinds of mistakes that I see in my students' writing all the time. And I'm going to give some examples, and it might be easier for the listeners to follow along with me if they could write down the examples that I give. So the first type of error is called a sentence fragment. Now what is a fragment?"

AA: "A little piece of something."

LB: "A little piece of something. So a sentence fragment is a little piece of a sentence. It's not a complete sentence. So let me give you the most common example of a sentence fragment that I see in people's writing all the time. It goes something like this: 'I never eat chocolate. Because I'm allergic to it.' Do you see the problem?"

AA: "Yes. That really should be one sentence."

LB: "That really should be one sentence, right. Now the first part — 'I never eat chocolate (period)' — that's fine, because that is a sentence. It has the subject 'I', and then it has the verb part 'never eat,' OK? So that's a complete sentence.

"The problem is the second part, 'because I'm allergic to it.' That can't stand alone as a sentence. What you have to do is you have to connect it to the complete sentence that came before it. When it stands by itself, it's called a dependent clause, or a subordinate clause. And the way that you fix a problem like this is that you take that dependent clause and you attach it to an independent clause, which is the same thing as a full sentence."

AA: "Wouldn't some people say there should be a comma in there, between those two clauses?"

LB: "No, no, no. Because if you put a comma in there, what you're doing is creating a different kind of sentence error, which is called a comma splice. In a comma splice, you have two sentences, two complete sentences that are separated by a comma. But what they should have in between is a period. So an example would be something like this: 'I never eat chocolate, I'm allergic to it.' Do you see how each of those parts is a complete sentence? So according to the rules of punctuation, we cannot use a comma to separate those two parts of the sentence."

AA: "So now we've gotten through the fragment and the comma splice. So what's next?"

LB: "Next we have what's called a run-on sentence. A run-on sentence consists of two independent clauses. And, remember, an independent clause is the same thing as a sentence. So it's two independent clauses that are not separated by any punctuation. So you have something like: 'I never eat chocolate I'm allergic to it.' In that case you can even hear that it's wrong. Because to say 'I never eat chocolate I'm allergic to it' doesn't even sound right. If we say it this way, though, 'I never eat chocolate (pause) I'm allergic to it,' you can actually hear where the period is supposed to go, right?"

AA: "Right."

LB: "It goes in the middle, between the two sentences."

AA: "OK, we've got fragment, comma splice, run-on sentence, and the fourth kind of sentence error is ... ?"

LB: "The stringy sentence. Let me give you an example of a stringy sentence: 'I never eat chocolate because I'm allergic to it, and I don't like nuts either, so I never eat them, but I'm not allergic to them, so last week I went out and I bought some nuts.' Now what do you think is wrong with that?"

AA: "Is that all one sentence?"

LB: "Yes, that is a stringy sentence. What we have there is a whole string of sentences, of independent clauses. All of them are separated by a comma and a conjunction: and, so, but. And as long as you punctuate it correctly with a comma and a conjunction, it isn't wrong. But you can hear that it just doesn't sound right. It sounds like somebody who's just babbling. And it's not considered good writing.

"Good writing is writing where you have a lot of variety in your sentences. Some of them are short. Some of them are long. Some of them are simple. Some of them are compound. Some of them are complex. So it's not static. It isn't symmetrical, OK? There is a lot of variety and a lot of different rhythms. This is what we consider to be good writing."

AA: Lida Baker writes textbooks for English learners, and she teaches in the American Language Center at the University of California, Los Angeles.

Internet users can find all of her previous segments at voanews.com/wordmaster. And the e-mail address for Wordmaster is word@voanews.com. I'm Avi Arditti.