cần phải

Really Need to

Level 2

cần phải combines 'need' and 'must' to express that an action is absolutely necessary.

How It Works

The pattern cần phải is a compound modal verb that expresses a pressing, urgent necessity. It is created by stacking two words:

  • cần: internal necessity or personal need
  • phải: external obligation or rule

By combining them, it implies both a personal need and an external requirement, often used as a generalized urgent 'must'. It sits at the very top of the obligation ladder, meaning 'absolutely must' or 'really need to'.

Structure:

  • Statement: Subject + cần phải + Verb / Adjective
  • Yes/No Question: Subject + có cần phải + Verb / Adjective + không?

Important Rules:
1. Verbs and Adjectives: Unlike cần, which can take a noun (e.g., Tôi cần tiền - I need money), cần phải must attach directly before a main verb or an adjective (since adjectives work like verbs in Vietnamese, no là is needed, e.g., cần phải cẩn thận - really need to be careful). To use a noun, add the verb có (e.g., Tôi cần phải có tiền - I really need to have money).
2. Not just for politeness: A common misconception is that adding phải just makes the sentence more formal. In reality, it changes the degree of obligation, making it mandatory or urgent. Using it for a mild suggestion sounds unnaturally aggressive.
3. Negation: To say 'don't need to' or 'don't have to', use không cần, không cần phải, or không phải. (Note that while không phải + Verb means 'don't have to', không phải + Noun means 'is not'). To express 'must not' (prohibition), use không được.
4. Passive Voice: It is frequently used in passive constructions with được or bị (e.g., cần phải được giải quyết - really needs to be resolved).

Examples (4)

  1. Anh cần phải cẩn thận hơn.

    You really need to be more careful.

    Word by Word: Brother need must careful more.

    Shows a strong, urgent advice or obligation.

  2. Chúng ta cần phải đi sớm hơn.

    We absolutely must leave earlier.

    Word by Word: We need must go early more.

    Expresses that leaving early is both a personal necessity and an external requirement.

  3. Bạn cần phải học chăm chỉ hơn.

    You really need to study harder.

    Word by Word: Friend need must study hard more.

    A strong imperative statement, much stronger than just using 'cần' or 'phải' alone.

  4. Tôi không cần phải làm việc hôm nay.

    I don't have to work today.

    Word by Word: I not need must do work today.

    Demonstrates the correct way to negate the pattern when the obligation is removed.

Common Mistakes

  • Using 'cần phải' directly with a noun object.

    Tôi cần phải một ly cà phê.
    Tôi cần một ly cà phê.

    Because English speakers say 'I need a coffee', they sometimes use cần phải with a noun. However, cần phải must be followed by a verb. If you want to use a noun, just use cần, or add a verb like 'uống' (to drink).

  • Placing the modal after the verb.

    Tôi đi cần phải.
    Tôi cần phải đi.

    Like in English, modal verbs in Vietnamese must be placed directly before the main verb they modify.

  • Using 'không được' (not allowed) when you mean 'don't have to'.

    Different MeaningBạn không được đi làm hôm nay vì là ngày nghỉ.
    Bạn không phải đi làm hôm nay vì là ngày nghỉ.

    This sentence is correct, but it says you are not allowed to work today. If you want to say that an action is unnecessary rather than forbidden, use không phải or không cần phải.

How It Connects

Tap a pattern to see what it builds on and what it leads to.

cần phảiLevel 2Really Need to

Learn This First

To understand 'cần phải', you first need to know its two component parts: 'cần' (to need) and 'phải' (must/have to). This pattern simply stacks these two concepts to create a more emphatic sense of necessity.

Words in This Pattern