Quên: Forget and Fail to Do

Vietnamese quên covers losing access to information, failing to carry out an intended action, and leaving an object behind. Quên tên means forget a name, quên gọi điện means forget to call, and quên điện thoại ở nhà means leave one's phone at home. There is no conjugation table for forget/forgot/forgotten: time and event structure come from aspect markers, particles, complements, and context.

This page contrasts those constructions with nhớ “remember/miss”. The next predicate, nói “say/speak”, belongs to speech and content introduction and receives its own page rather than being folded into this one.

The main construction choices

The same English verb appears in every row, but the Vietnamese frame identifies whether the missing element is knowledge, an action, an object, or something the speaker wants dismissed.

Forgetting information and facts

A noun directly after quên can name information no longer available in memory: a name, date, password, face, rule, or language. Context determines whether the loss is momentary or lasting. Quên gần hết and quên dần describe degree or gradual loss.

Facts can follow quên là in ordinary speech or quên rằng in careful and formal language. A bare clause is possible, but an introducer helps when the clause is long or its boundary could be unclear.

Không nhớ and quên overlap but present the situation differently. Tôi không nhớ mã số reports current inability to recall it. Tôi quên mã số rồi presents a loss from a previously available state. Chưa nhớ ra leaves open the prospect of retrieval.

Forgetting to perform an action

The productive frame quên + VP means an intended or required action was omitted. Vietnamese does not insert an infinitive marker corresponding to English to. The following predicate begins the omitted action directly.

This differs from forgetting that an action already happened. Compare Tôi quên gửi thư “I forgot to send the letter” with Tôi quên là mình đã gửi thư “I forgot that I had sent the letter.” In the first, the sending did not occur; in the second, it occurred but is absent from the speaker's memory.

Some speakers use quên không + VP, as in quên không khóa cửa, to mean “forget to do,” with không describing the action that failed to occur. The pattern is established but structurally easy to misread, especially inside a negative sentence. Learners should prefer the clearer quên khóa cửa unless the local usage and context are secure.

Leaving an object behind

Quên + object + place can mean leave an object somewhere unintentionally. Để quên + object + place makes the “left behind” result especially clear. The location commonly follows ở, trên, trong, or a bare contextual place phrase.

English “I forgot my phone” can mean either “I left it behind” or “I failed to bring it.” Vietnamese usually states the relevant scene: Tôi quên điện thoại ở nhà or Tôi quên mang điện thoại. A bare Tôi quên điện thoại is possible in a clear departure context, but it gives the listener less information.

Mất, bẵng, đi, and other resultative additions

Quên mất is extremely common. Mất presents the forgetting as an inadvertent or complete result and often accompanies an apology or sudden realization. It is not literally the independent verb “lose” in this construction.

Quên bẵng means forget entirely for a stretch of time, often until something triggers the memory. It is expressive but ordinary. Quên khuấy has a similar emphatic value and is especially associated with colloquial Northern usage (regional: Northern Vietnam; informal).

Quên đi is often directive: “forget it,” “let it go,” or “put it behind you.” Tone ranges from comforting to dismissive. Thôi, quên chuyện đó đi may soothe a friend; a sharp Quên đi! can reject a proposal as impossible (informal).

Other useful collocations include quên trước quên sau “be very forgetful,” quên ăn quên ngủ “be so absorbed that one forgets to eat and sleep,” and quên mình “forget oneself/selflessly disregard oneself.” The last can be laudatory in làm việc quên mình “work selflessly” but needs context.

Aspect, change, and negation

Đã quên places the loss before the reference point. Quên rồi presents forgetting as the current relevant result. Vừa quên mất marks a very recent lapse. Because forgetting is usually a transition or result, bare đang quên is uncommon for one sudden lapse; đang dần quên is natural for gradual fading.

Không quên can promise continued memory or attention: Tôi không quên đâu “I won't forget.” Chưa quên says the memory has not faded up to now and can be emotionally marked: Tôi vẫn chưa quên chuyện ấy “I still haven't forgotten that.”

A five-way reference set

The complement tells you what failed

Quên mang identifies an omitted action; quên là... a forgotten fact; để quên...trên bàn an object left behind. The forms around quên do the work that English often leaves to context.

Common Mistakes

1. Confusing an omitted action with a forgotten completed event.

2. Copying English “forget about” with về. A specific forgotten item normally follows quên directly.

3. Leaving the location implicit when English “forgot my phone” means “left it behind.”

4. Using đang for a punctual lapse without a gradual expression.

Key Takeaways

• Quên + information describes lost memory; quên + VP describes an omitted action.
• Use quên là đã + VP when the action happened but the memory of it is lost.
• Để quên + object + place clearly expresses leaving something behind.
• Quên mất, quên bẵng, and quên đi add accidental completion, total lapse, and dismissal respectively.
• Prefer explicit frames over copying English forget about, forgot my phone, or infinitive syntax.