What is Once in English? The usage and practice exercises with detailed answers

While Once may not be among the most common English vocabulary lists, mastering its common usage and collocation will enhance your English proficiency. What is Once in English and what are its structures? Let's explore with PREP below!

I. What is Once in English?

What is Once in English? According to the Cambridge Dictionary, Once has two main roles - as an adverb and conjunction. Once conveys the meaning of having done or experienced something a certain number of times in the past. For example:

• I went sailing once, but I didn’t like it. 
• We have lunch at a restaurant together once a month. 
• Once you’ve tried their ice cream, you’ll be back for more. 

II. The usage of Once in English

Let’s join PREP to check out the common usage of Once!

1. Once serves as an adverb

1.1. Having done something in the past

Once can be used at the end or beginning of a sentence to express things that were done in the past:

• I went to Disney World once. 
• I visited New York City once, and I fell in love with its energy. 

1.2. Adverb of frequency

When used as an adverb indicating frequency, Once is often used with words like:

• Once + a + singular noun. For example: I go swimming once a week.
• Once + every + plural noun. For example: We have a team meeting once every two weeks to discuss our progress.

2. Once serves as a conjunction

Once can also function as a conjunction, used to join two simple sentences together to form a complex sentence with meaning. For example:

• Remember that you won’t be able to cancel the contract once you’ve signed. 
• Once I’ve found somewhere to live I’ll send you my address. 

III. Differentiate between Once and One

Although "Once" and "One" may seem similar at first glance, their meanings, parts of speech, and usage are substantially different. Let's dive into those differences in the table below:

IV. Common collocations of Once in English

Let’s uncover which are common collocations of Once with PREP in the below table!

V. Exercises on Once in English with detailed answer

Strengthen your knowledge of the Once structure with the following two practice exercises right away!

1. Exercises

Exercise 1: Fill in the blanks with one or once:

1. I need  _____more pen to complete the set.
2. Can you pass me  _____of those books on the shelf?
3. She baked  _____delicious cake for the party, and everyone loved it.
4.  _____he graduated from college, he started working for a tech company.
5. She only tried sushi  _____, and she didn’t like it at all.
6. I’ll help you with your project  _____I finish mine.
7.  _____of my favorite movies is “The Shawshank Redemption.”
8. I have only  _____ticket left for the concert, so who wants to go with me?

Exercise 2: Rewrite the following sentences with once without changing the original meaning:

1. I visited London for the first time last year.
2. She had never been on a roller coaster before.
3. The children only saw snow when they went to the mountains in winter.
4. We experienced a total solar eclipse in 2017, and it was amazing.
5. He tasted sushi for the very first time during his trip to Japan.

2. Answer keys

Exercise 1:

1. one
2. one
3. one 
4. Once
5. Once
6. once
7. One
8. one

Exercise 2:

1. I visited London once last year.
2. She had never been on a roller coaster once.
3. The children saw snow once they went to the mountains in winter.
4. We experienced a total solar eclipse once in 2017, and it was amazing.
5. He tasted sushi once during his trip to Japan.

Hopefully, the knowledge about Once in English that PREP shared in this article has helped you expand and deepen your understanding of what Once is and how to use Once. If you have any questions, please leave a comment and PREP will respond as soon as possible!