Using Do vs. Does Properly in Questions and Sentences

The main definition of “do” is “to accomplish an action.” The main definition of “does” is “a reference to the accomplishment of another.” Both words mean basically the same thing, because “does” is the third person singular present tense version of “do.” The difference is in how each word gets used.

Since “does” is really just a form of “do,” both words have a lot in common.

• Both are verbs, or action words.
  What do you do on days off?
  How does that clock work?
• Both are present tense.
  I do love this game.
  She does want to come over now.
• Both have the same general definition.
  I do my hair before school.
  She does her hair before school.
• Both are put in the same place in sentences and questions.
  Do you like chicken nuggets?
  Does your mom like chicken nuggets?
• Both can replace a main verb when the meaning is obvious.
  How do you do that?
  How does he do that?

The dictionary definition of “do” actually includes several definitions, like “to perform,” “to bring about,” and “to solve,” while “does” only has one definition. The use of “do” and “does” is the key difference between the two words.

• “Do” is used for plural subjects like “you,” “we,” “they,” “these,” “those,” or “John and I,” as well as with “I.”
  Example: They do not like snakes.

• “Does” is used for singular subjects like “he,” “she,” “it,” “this,” “that,” or “John.”
  Example: John does not like snakes
• “Do” is used to form imperative sentences, or commands.
  Example: Do your homework.
• “Does” is never used to form imperative sentences.
  Example: Does your homework. (incorrect)

When you use “do” in a sentence or “does” in a sentence, it will typically not be the first word. It can, however, fall anywhere else in the sentence. Can you see how “do” is used for plural subjects and “does” for singular subjects?

• I want to do my best in this race.
• That does not make any sense.
• We do not care about imaginary creatures.
• I do love a good comedy.
• They can do better than that.
• He believed he could do it.
• The machine does everything for us.
• If you do what I tell you, it will be fine.
• Jack and Jill do whatever they want on Tuesdays.

In questions, “do” or “does” usually starts the sentence, but it doesn’t have to. For a simple interrogative sentence, or question, “do” or “does” is typically followed by the subject, and then the conjugated verb.

Questions with “do” or “does” as the first word usually elicit a “yes” or “no” answer. If the question starts with “who,” “what,” “where,” “when,” or “why,” the word “do” or “does” can come after that question word.

• What does Jenny want for breakfast?
• Do chickens usually fly?
• Why does your coat have ten zippers?
• Does California have many beaches?
• Where do you find pink dolphins?
• Does watching TV make kids violent?
• When does she normally come home from work?
• Do we enter from the front door?
• Who does he think he is?
• Do they know they’re being watched?
• How many times do they have to push that button?

While there are many rules to remember when it comes to using the words “do” and “does,” there are some things you’ll never do with them.

• Don’t add an “s” to the main verb when using “do” or “does.”
• Don’t use “do” or “does” to start open-ended questions.
• Don’t use “do” or “does” with the verb “to be.”

Learning basic English grammar takes time, but anyone can become great at speaking and writing in English. See how much you’ve learned about grammar topics like “do” vs. “does” by taking a basic English grammar test.