Common Mistakes with the Verb ‘buy’

The verb buy is one of the most frequently used verbs in English, yet it causes confusion for many learners. The main problem is that buy is an irregular verb: its past tense is bought, not “buyed,” and its past participle is also bought. This article explains the correct forms of buy, shows you how to avoid the most common errors, and gives you practical examples for real conversations, emails, and writing.

Quick Answer: The Correct Forms of ‘buy’

• Base form: buy (used for present tense, infinitive, and imperative)
• Past tense: bought (never “buyed”)
• Past participle: bought (used with have, has, had)
• Present participle / gerund: buying
• Third person singular: buys

Example: “I buy groceries every Saturday. Yesterday, I bought vegetables. I have bought them from that shop for years.”

Comparison Table: Correct vs. Incorrect Forms

Natural Examples of ‘buy’ in Context

Everyday Conversation (Informal)

• “I bought a new phone yesterday. It was on sale.”
• “Have you bought the tickets for the concert yet?”
• “She always buys coffee on her way to work.”
• “We’re buying a house next month.”

Formal / Written English (Email, Reports)

• “The company bought new equipment for the laboratory.”
• “We have bought the rights to distribute the product in Europe.”
• “Please confirm that you have bought the necessary insurance.”
• “The shares were bought at a favorable price.”

Nuance: ‘buy’ vs. ‘purchase’

In everyday conversation, buy is natural and common. Purchase is more formal and often used in business, legal, or official contexts. For example, you would say “I bought milk” to a friend, but “The company purchased the building” in a report. Using buy in formal writing is not wrong, but purchase can sound more professional.

Common Mistakes with ‘buy’

Mistake 1: Using “buyed” for the past tense

This is the most frequent error. Buy is irregular, so the past tense is bought, not “buyed.”

Incorrect: “Yesterday I buyed a new jacket.”
Correct: “Yesterday I bought a new jacket.”

Mistake 2: Using “bought” as the base form after modals or “will”

After modal verbs (can, should, must, will), always use the base form buy.

Incorrect: “I will bought groceries tomorrow.”
Correct: “I will buy groceries tomorrow.”

Incorrect: “You should bought a gift.”
Correct: “You should buy a gift.”

Mistake 3: Confusing “bought” with “brought”

Bought is the past of buy (to purchase). Brought is the past of bring (to carry or come with). These sound similar but have different meanings.

Incorrect: “I brought a new laptop from the store.” (unless you carried it from somewhere else)
Correct: “I bought a new laptop from the store.”

Correct use of brought: “I brought my laptop to the meeting.”

Mistake 4: Forgetting the past participle in perfect tenses

In present perfect (have/has) and past perfect (had), you must use the past participle bought.

Incorrect: “I have buy a new car.”
Correct: “I have bought a new car.”

Incorrect: “She had buy the tickets before the price went up.”
Correct: “She had bought the tickets before the price went up.”

Better Alternatives and When to Use Them

When to use “buy”

Use buy in most everyday situations. It is simple, direct, and appropriate for conversation, informal emails, and general writing.

When to use “purchase”

Use purchase in formal or professional contexts, such as business reports, contracts, official documents, or academic writing. It adds a tone of formality.

When to use “get”

In very casual conversation, native speakers often use get instead of buy. For example: “I need to get some milk.” This is fine with friends but avoid it in formal writing.

When to use “invest in”

If you are buying something valuable or long-lasting, you can say invest in. For example: “We decided to invest in a new computer.” This implies a thoughtful purchase.

Mini Practice: Test Yourself

Complete each sentence with the correct form of buy (buy, buys, buying, bought). Answers are below.

1. She usually __________ organic vegetables from the farmer’s market.
2. Last weekend, we __________ a new sofa for the living room.
3. They have already __________ the plane tickets for their vacation.
4. I am __________ a gift for my mother’s birthday.

Answers:

1. buys
2. bought
3. bought
4. buying

Frequently Asked Questions (FAQ)

1. Is “buyed” ever correct?

No. “Buyed” is not a standard English word. The correct past tense and past participle is always bought.

2. What is the difference between “bought” and “brought”?

Bought is the past of buy (to purchase something). Brought is the past of bring (to carry something to a place). For example: “I bought a cake at the bakery, and I brought it to the party.”

3. Can I say “I have boughten”?

No. “Boughten” is an old or dialect form that is not used in standard modern English. Always use bought as the past participle.

4. Do I need to use “purchase” instead of “buy” in formal writing?

Not necessarily. Buy is acceptable in most formal writing, but purchase can sound more professional in business or legal documents. Choose based on the tone you want.

Final Tips for Using ‘buy’ Correctly

• Memorize: buy → bought → bought (like bring → brought → brought).
• After will, can, should, must, may, might, always use buy, not bought.
• In perfect tenses (have, has, had), always use bought.
• Practice with real sentences: write three sentences using bought in the past tense and three using have bought.

For more help with verb forms, visit our Verb Forms Explained section. If you have questions about other common verb errors, check our Common Verb Mistakes category. You can also read our FAQ for quick answers to common questions.