Must Modal Verb: Meaning, Usage, and Examples

Meaning 1：be obliged to (must)

must 🔊

/mʌst/

modal v.

Used when you have no choice but to do something. It's a very strong need or rule.

be obliged to 🔊

➕

/biː əˈblaɪdʒd tuː/

modal v.

Used to indicate that something is necessary or very important, often due to a rule, law, or strong requirement.

📁 Category：Social Roles 🔖 Level：elementary

📘 Details & Usage

📖 Root Explanation

From Old English 'mōste', past of 'magan' (to be able), shifted from permission to obligation.

💡 Mnemonic

MUST: think of a stop sign with 'MUST' written on it, reminding you of a rule you cannot ignore.

📖 Example

You must finish your homework before playing video games. 🔊 It is necessary for you to complete your homework before you are allowed to play video games.

🔗 Collocations

must do – something that is essential or required

must have – a necessary item or quality

must be – used to express a logical conclusion or strong probability

🔄 Synonyms

have to (modal phrase) – Expresses necessity or obligation, often interchangeable with 'must'.

need to (modal phrase) – Indicates that something is required or essential.

be required to (verbal phrase) – Formal way to express that something is demanded by authority.

🚫 Antonyms

may (modal v.) – Indicates permission or possibility, opposite of obligation.

can (modal v.) – Expresses ability or possibility, not necessity.

optional (adj.) – Describes something that is not required.

🌱 Derivatives

must-have (n.) – something that is considered essential

must-see (adj./n.) – something that is highly recommended to be seen

must-read (adj./n.) – something that is highly recommended to be read

📖 Cultural Story

In modern English, 'must' is central to legal and moral language, expressing a strong necessity. It is rarely used in past tense; 'had to' substitutes. It also appears in 'must-have' for essential items.