You may have heard that two wrongs don't make a right. That's certainly true of grammar. Applying two negative statements to the same subject is a double negative, almost always a grammatical no-no guaranteed to confuse your readers.
Suppose you said, "I don't got no money." The phrase "I don't got money" means you don't have money, certainly. So does the phrase "I got no money." But, if you DON'T got NO money, you're using a double negative. In effect, you're saying the thing you don't have is "no money." So, it starts to sound like you have some money.
In fact, it doesn't mean anything. Double negatives are bad English, at least when it comes to writing. Conversational context usually clarifies double negatives in speech, but when written down, they create structurally meaningless sentences.
Fundamentally, double negatives are nonsense in English, because they cancel one another's meaning. This creates a positive sentence that didn't require the negatives in the first place.
We'll borrow from classic rock for an example:
"We don't need no education."
"We don't need education" and "we need no education" both say the same thing. Saying both at once means they cancel each other out, and we DO need education. Maybe this whole time Pink Floyd was telling us they needed enough education to understand why double negative usage is wrong!
Interestingly, in some languages -- like Russian, Macedonian, Serbian and Croatian -- if you want to express a negative connotation, you need to use a negative throughout the phrase or sentence. Not so in English. For English speakers, one grammatical clause only requires one negative.
In short, they're too long. Since a double negative expresses a positive - "I don't want no cake" technically means you do want cake - proper English requires you simply write a positive sentence: "I want cake."
By itself, that would be bad enough. Good English writing is about expressing your ideas in short, clear terms. But, double negatives also create confusion. In conversation, English speakers know that "I don't want no cake" means the same as "I don't want cake." That means the written meaning of a double negative differs from the spoken meaning. That's a big problem and one you must avoid.
Test your double negative knowledge! For each of the example sentences below, identify the double negative -- there may be more than one per sentence -- and offer a grammatically correct alternative sentence.
A downloadable PDF of this exercise is also provided below.
- I don't got no friends.
- I couldn't hardly wait to get to the party.
- I did not barely understand what you were saying.
- I hardly never heard the bells ring.
- Neither fish nor chicken weren't at the party.
- It never doesn't rain in Florida.
- I couldn't not cry at the sad movie.
- I didn't not want to go to the mall.
- I wasn't hardly finished when the bell rang.
- We never don't go for ice cream after a movie.
- "Don't" and "no" are both negatives. Instead, the sentence should read, "I've got no friends" or "I don't have friends."
- Both "couldn't" and "hardly" are negatives. Try instead, "I could hardly wait" or "I couldn't wait."
- Both "did not" and "barely" are negative. "I did not understand" and "I barely understood" would both have been acceptable.
- "Hardly" and "never" are both negatives. "I hardly ever heard" or "I never heard" both work.
- This sentence contains a double negative because "neither" and "weren't" are both negatives. "Neither fish nor chicken were at the party" would be fine, as would "Fish and chicken weren't at the party."
- "Never" and "doesn't" form our double negative. "It doesn't rain" and "It never rains" would both work fine.
- This is an example of the author wanting the literal meaning of the double negative. "Couldn't" and "not" cancel each other out, meaning the author could cry at the sad movie. The double negative phrasing is still awkward. A better choice would be, "I had to cry at the sad movie" or "I couldn't help crying at the sad movie."
- "Didn't" and "not" cancel each other, making the sentence unclear. Depending on the author's intent, either "I wanted to go to the mall" or "I didn't want to go to the mall" would have worked.
- This sentence may sound just fine if you're from parts of the American South. However, what works in casual conversation isn't always valid written down, and "wasn't" and "hardly" form a classic double negative. Try "I was hardly finished" or "I wasn't finished" to be grammatically accurate.
- Here's another positive statement expressing itself through an invalid double negative. Instead, simply say, "We always go for ice cream after the movie."