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Grammar Mistakes

An Hour vs. A Hour: Avoid This Common Grammar Mistake!

In the English language, you might sometimes struggle with the correct usage of indefinite articles, such as “a” and “an.” One particular example that can be confusing is whether to say “an hour” or “a hour.” The lesson covers the main differences between “an hour” and “a hour,” including definitions and tips to remember the differences.

An Hour vs. A Hour: Make Sure You Get It Right!

Quick Tips:

The correct phrase is “an hour,” not “a hour.”

  • Use “an” before words that start with a vowel sound (like “hour”).
  • Use “a” before words that start with a consonant sound (like “house”).
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An Hour vs. A Hour – Created by 7ESL

An Hour vs. A Hour: Definition, Usage

An Hour:

  • Meaning: Refers to a period of 60 minutes.
  • Use: “An” is used instead of “a” before words that start with a vowel sound. In “hour,” the “h” is silent, so the word begins with a vowel sound (“our”).
  • Example: “I’ll be there in an hour.”
  • Explanation: “An” is the correct indefinite article here because the “h” in “hour” is not pronounced, and the word starts with a vowel sound.

A Hour:

  • Incorrect: “A hour” is not correct because “a” is used before words that begin with a consonant sound. Since “hour” starts with a silent “h” and has a vowel sound (“our”), “an” should be used instead.
  • Example of Incorrect Use: “I’ll call you back in a hour.”

Tips to Remember the Differences

  • Identify the first sound of the word: if it begins with a vowel sound, use ‘an’; if it starts with a consonant sound, use ‘a’
  • Always consider the sound and not the written form of the word
  • Remember that ‘hour’ has a silent ‘h,’ making it an exception to the standard rule

An Hour vs. A Hour: Examples

Example 1:

  • Correct: You should arrive at the airport an hour before your flight.
  • Incorrect: You should arrive at the airport a hour before your flight.

Example 2:

  • Correct: The movie will start in an hour, so we have some time to grab a snack.
  • Incorrect: The movie will start in a hour, so we have some time to grab a snack.

Example 3:

  • Correct: She completed the task in just an hour, which is quite impressive.
  • Incorrect: She completed the task in just a hour, which is quite impressive.

Example 4: 

  • Correct: I will be ready in an hour for the meeting.
  • Incorrect: I will be ready in a hour for the meeting.

Example 5:

  • Correct: The drive to the beach takes about an hour in light traffic.
  • Incorrect: The drive to the beach takes about a hour in light traffic.

Example 6:

  • Correct: He finished his assignment in just an hour.
  • Incorrect: He finished his assignment in just a hour.

A University vs. An University

A university” is the correct usage because “university” begins with the consonant sound “ju”. Therefore, “a university” is the grammatically correct form.

  • Correct: He is studying at a university known for its engineering program.
  • Incorrect: He is studying at an university known for its engineering program.

A Uniform vs. An Uniform

A uniform” is the correct usage because “uniform” begins with the consonant sound “ju”. Therefore, “a uniform” is the grammatically correct form.

  • Correct: The soldier put on a uniform before heading out for duty.
  • Incorrect: The soldier put on an uniform before heading out for duty.

A European vs. An European

A European” is the correct usage because “European” begins with the consonant sound “ju”. Therefore, “a European” is the grammatically correct form.

  • Correct: The company hired a European consultant to provide expertise.
  • Incorrect: The company hired an European consultant to provide expertise.

 A UFO vs. An UFO

When dealing with acronyms or abbreviations, it’s essential to focus on how they sound rather than their spelling. “UFO” (Unidentified Flying Object), where “U” is pronounced like “you.” Therefore “a UFO” is the grammatically correct form.

  • Correct: The witness claimed to have seen a UFO hovering in the night sky.
  • Incorrect:The witness claimed to have seen an UFO hovering in the night sky.
A2 Knowledge Check · 5 questions

An Hour vs. A Hour: Avoid This Common Grammar Mistake! — Practice Quiz

1 / 5
Q1

Question 1: Which sentence uses "an" correctly?

Question 1 options
"An hour" is correct because the "h" in "hour" is silent, so the word begins with a vowel sound. The other sentences incorrectly use "an" before words that start with consonant sounds.
Q2

Question 2: We use "a" or "an" based on the first letter of the word, not its sound.

Question 2 options
This is false. The article explains that you should always consider the sound, not the written form of the word. For example, "hour" starts with the letter "h" but uses "an" because the "h" is silent and the word begins with a vowel sound.
Q3

Question 3: The drive to the beach takes about ___ in light traffic.

Question 3 options
"An hour" is correct because the "h" in "hour" is silent, making the word start with a vowel sound. We use "an" before vowel sounds.
Q4

Question 4: Match each word to the correct indefinite article.

Question 4 options

Select an item on the left, then tap its match on the right.

{""content"": ""a (pronounced h sound)""
Q5

Question 5: Why is "an" used before "hour" instead of "a"?

Question 5 options
The "h" in "hour" is silent, so the word begins with the vowel sound "our." Since we use "an" before vowel sounds, "an hour" is correct.

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