open up

IPA/ˈəʊpən ˈʌp/
IPA/ˈoʊpən ˈʌp/

open up — phrasal verb

  • open upbase form
  • opens up3rd person singular
  • opening up-ing form
  • opened uppast simple

1. to pull, push, lift, or cut apart the parts of something that is closed, sealed,

1.片語動詞及物 / 不及物A2
釋義

to pull, push, lift, or cut apart the parts of something that is closed, sealed, or locked, so that the inside can be reached, looked at, or used. Often used when some effort or force is needed.

例句

The doctor opened up the wound to remove the small pieces of glass.

collocation: open up a wound / a package / a container

Adina opened up the suitcase on the bed and pulled out her clothes.

transitive: open up + [container]

同義詞
  • open

    more neutral and general; 'open up' is slightly more informal or emphatic

  • cut open

    more specific, implies using a blade

  • unseal

    formal register, used for official or sealed items

反義詞
  • close up

    to shut something completely, opposite of opening

  • seal

    to close something tightly so the inside cannot be reached

文法句型

open up + noun phrase (container, door, package, wound)

open + noun phrase + up

open up (intransitive)

用法筆記

More informal than the plain verb 'open'. The object can come between 'open' and 'up' (open the box up). In medical contexts, 'open up a wound' is the standard phrasing for surgically reopening.

常見錯誤

She opened up the door with her key.
She opened the door with her key.
💡For routine everyday actions like unlocking a door, use 'open' alone. 'Open up' fits when some effort is involved.

2. to begin serving customers at a shop, restaurant, or café for the current day, e

2.片語動詞及物 / 不及物A2
釋義

to begin serving customers at a shop, restaurant, or café for the current day, especially by unlocking the doors and preparing the premises for people to enter.

例句

The bakery opens up at six in the morning every day except Sunday.

intransitive: open up at [time]

Felix opened up the café early because of the big street festival that day.

transitive: open up + [business]

同義詞
  • open

    more neutral; 'open up' feels slightly more informal and thorough

反義詞
  • close up

    to shut the business at the end of the day

文法句型

open up (at + time)

open up + noun phrase (shop, store, café)

open + noun phrase + up

用法筆記

Transitive when the speaker says which business is being opened; intransitive when the business is already known from context. Contrasts with 'close up' for the end of the day. Use the simple present tense for habitual opening times.

常見錯誤

The new restaurant will open up next week.' (if you mean opening for the first time)
The restaurant opens up at ten every morning.
💡For daily opening times, use the simple present. For a brand-new business, see sense 3.

3. to create and start running a new company, store, restaurant, or other commercia

3.片語動詞及物 / 不及物B1
釋義

to create and start running a new company, store, restaurant, or other commercial venture that did not exist in that location before.

例句

After years of baking at home, Allison opened up a cake shop on Market Street.

transitive: open up + [type of business]

A new yoga studio opened up in the old building where the library once stood.

intransitive: [business] opened up + [location]

同義詞
  • set up

    focuses on the preparation stage

  • establish

    more formal, often used for larger companies

  • start

    more general, can apply to any venture

反義詞

文法句型

open up + noun phrase (a shop, restaurant, business, store)

open up (intransitive — a new restaurant opened up)

用法筆記

Distinguish from sense 2: sense 2 is about beginning the day's business at an existing shop; sense 3 is about founding a new enterprise for the first time. Intransitive use describes a new business appearing in a location.

常見錯誤

I opened up my computer to check emails.
I opened up a coffee shop last year.
💡'open up' for starting a business is different from physically opening a device (sense 1).

4. when an event, policy, or decision creates new opportunities, choices, or possib

4.片語動詞及物B1
釋義

when an event, policy, or decision creates new opportunities, choices, or possibilities that did not exist before, making them available for people to use or enjoy.

例句

The new railway line opened up job opportunities for thousands of people in the region.

collocation: open up opportunities / open up markets

Learning Mandarin opened up better job opportunities for Felipe in Shanghai.

[skill/experience] + opens up + [opportunities]

同義詞
  • create

    broader, less vivid; 'open up' implies something was previously blocked

  • unlock

    more figurative, about releasing potential that was trapped

反義詞
  • block

    deliberately prevent access or possibility

  • close off

    remove the chance to use something

文法句型

open up + noun phrase (opportunities / markets / possibilities / doors)

用法筆記

Transitive only — requires a direct object. Subject is typically an event, policy, technology, or decision, not a person acting directly. Often used with nouns like 'opportunities', 'markets', 'possibilities', 'doors', or 'choices'. Frequently positive in tone.

常見錯誤

The new policy opened up the problem of funding.
The new policy created the problem of funding.
💡'open up' is used for positive or neutral new possibilities, not for creating difficulties or problems.

5. when a job, position, or opportunity becomes available, it appears or is freed f

5.片語動詞不及物B1
釋義

when a job, position, or opportunity becomes available, it appears or is freed for someone to take or use, often unexpectedly or at a specific time.

例句

A teaching position at the international school opened up just when Wren needed it.

intransitive: a position / job / spot opens up

After the manager retired, several new roles opened up in the sales department.

同義詞
  • become available

    more literal, less idiomatic

  • appear

    broader, not limited to job contexts

  • arise

    slightly more formal, suggests a natural emergence

反義詞
  • close

    stop being available

文法句型

[job / position / opportunity / spot / role] + opens up

用法筆記

Always intransitive — the job or opportunity is the subject, not the person who takes it. The subject is a desirable opening (job, role, spot, vacancy), not a problem or negative situation. Distinguish from sense 4, where someone actively creates the opportunity (transitive).

常見錯誤

The company opened up a new position for me.
A new position opened up at the company.
💡When a position becomes available on its own, use the intransitive pattern. For the company actively creating it, use sense 4 (transitive).

6. to bring hidden information, facts, or secrets to light so that people can learn

6.片語動詞及物B2
釋義

to bring hidden information, facts, or secrets to light so that people can learn about them, often through investigation or research.

例句

The journalist's investigation opened up evidence of illegal fishing in protected waters.

collocation: open up evidence / open up facts

Andrés opened up a hidden world of underground music when he launched his podcast.

collocation: open up a hidden world of [something]

同義詞
  • uncover

    more direct synonym, implies lifting a cover

  • disclose

    more formal, often used in legal or official contexts

  • expose

    stronger connotation of wrongdoing or scandal

反義詞

文法句型

open up + noun phrase (evidence / facts / secrets / details)

用法筆記

Subject is typically an investigation, study, inquiry, or inquisitive action. Unlike sense 4 (CREATE OPPORTUNITIES), the focus here is on exposing what was hidden rather than creating something new. Often used with abstract nouns like 'world', 'facts', 'evidence'.

7. to begin talking honestly about your personal thoughts, feelings, or problems, e

7.片語動詞不及物B1
釋義

to begin talking honestly about your personal thoughts, feelings, or problems, especially when you are usually private or shy about such topics and it takes time to feel comfortable enough.

例句

Leo opened up to his sister about how nervous he felt starting his new job.

pattern: open up + to + person + about + topic

It took hours of careful questions before Diego opened up about his childhood.

open up about [topic]

同義詞
  • confide

    stronger focus on trusting the listener with private information; used with 'in' (confide in someone)

  • unburden oneself

    more formal; emphasises relief after sharing worries

  • speak out

    more about expressing a public opinion rather than sharing personal feelings

反義詞
  • clam up

    informal opposite; means to suddenly stop talking or refuse to speak

  • shut down

    informal; means to stop communicating emotionally or to withdraw

文法句型

open up (about + topic)

open up (to + person)

open up (about + topic + to + person)

用法筆記

Intransitive only — never takes a direct object. Commonly followed by about + topic and/or to + person. The subject is someone who was previously guarded, shy, or hesitant about sharing. This sense implies emotional trust built over time.

常見錯誤

He opened up the secret to his friend.
He opened up about the secret to his friend.
💡This sense of 'open up' is intransitive; do not add a direct object. Use 'about' to introduce the topic.

8. when a wide, impressive view or open space appears in front of you as you move i

8.片語動詞不及物B1
釋義

when a wide, impressive view or open space appears in front of you as you move into a new position, especially after passing through a narrow or obstructed area.

例句

After climbing the hill, a beautiful lake opened up before Takeshi and his friends.

intransitive: view / valley / scene opens up before [someone]

When they reached the mountain top, the entire valley opened up beneath them.

preposition: opens up beneath / before / ahead

同義詞
  • spread out

    more neutral, less vivid

  • unfold

    suggests a gradual revealing, like petals or a map

  • come into view

    emphasises the observer's experience, not the scene's action

反義詞

文法句型

[view / scene / valley / landscape] + opens up + [preposition (before / beneath / ahead)]

用法筆記

Almost always used with a scenic or spatial subject (view, valley, landscape, panorama). Intransitive — the scene itself spreads out before the observer; no one actively opens it. Common prepositions: before, beneath, ahead, below.

9. to become wider or to make a narrow space wider by removing an obstacle, wall, o

9.片語動詞及物 / 不及物B2
釋義

to become wider or to make a narrow space wider by removing an obstacle, wall, or barrier, creating more room or an open area.

例句

The narrow dirt track opened up into a proper paved road near the village.

intransitive: narrow space opens up into [wider area]

Joon carefully opened up the hole in the fence so the pipe could fit through.

transitive: open up [opening/hole]

同義詞
  • widen

    more direct synonym, but lacks the idiomatic flavour

  • broaden

    similar but suggests lateral expansion rather than removal of an obstacle

  • expand

    suggests growth in all directions, not just width

反義詞
  • narrow

    to become narrower; the opposite direction

文法句型

open up + noun (transitive: make a space wider)

noun + open up + into + noun (intransitive: space becomes wider)

用法筆記

Often used with 'into' to describe what the wider space becomes ('opened up into a courtyard'). Differs from sense 8 (VIEW APPEARS): sense 8 is about a panoramic vista appearing suddenly; sense 9 is about physically expanding a space or a passage becoming wider.

常見錯誤

She opened up her eyes wide to see better.
She opened her eyes wide to see better.
💡'open up' is not used with body parts; use the simple verb 'open' instead.

10. to start firing from weapons such as guns, cannons, or missile launchers, especi

10.片語動詞不及物C1
釋義

to start firing from weapons such as guns, cannons, or missile launchers, especially in a battle, military conflict, or armed confrontation.

例句

The soldiers opened up with heavy machine guns when the enemy came closer.

military use: open up with [weapon]

The warship opened up on the enemy base at dawn, firing large shells.

open up on [target]

同義詞
  • open fire

    more common equivalent; 'open fire on' is the standard formal military phrasing

  • start shooting

    less formal, wider range of contexts including non-military

反義詞

文法句型

open up (on/at + target)

open up (with + weapon)

用法筆記

Almost exclusively found in military, police, or action-film contexts. The subject is a person, group, or military unit operating a weapon. The preposition 'on' or 'at' introduces the target; 'with' introduces the weapon type. Intransitive only.

常見錯誤

The soldiers opened fire up at the enemy.
The soldiers opened up at the enemy.
💡'open up' already includes the idea of firing; adding 'fire' is redundant.