Verb + đi

In Vietnamese, stringing verbs together is very common. Here, đi functions as a resultative particle, creating phrases similar to English phrasal verbs.

1. Verbs of Disposal and Removal
Attach đi to transitive verbs like vứt (throw), bán (sell), xóa (delete), or quên (forget) to emphasize that the object is completely gone. For example, bán đi means "to sell off."

2. Verbs of Motion
With verbs of motion, it indicates moving away from the speaker. This includes intransitive verbs like chạy (run) or bay (fly) (e.g., chạy đi = run away), as well as transitive verbs of carrying like mang or đem (e.g., mang đi / đem đi = to take away).

3. Loss of Consciousness or Life
Đi is heavily used with verbs of state to indicate passing into an unconscious, inactive, or dead state. Common examples include ngất đi (to faint), thiếp đi (to fall asleep/doze off), or chết đi (to die). Note that in everyday spoken Vietnamese, chết đi is most frequently heard as an aggressive imperative ("Go die!") or as part of an extreme intensifier.

4. Object Placement
If there is an object, đi usually goes after pronouns and bare or generic nouns (vứt rác đi = throw the trash away; vứt nó đi = throw it away). However, đi can naturally precede the object if it is a specific noun phrase (e.g., bán đi chiếc xe = sell off the car) or a long, complex one.

5. Adjectives of Diminishing State
When attached to adjectives, đi indicates a decreasing or diminishing change of state. While this often implies worsening (like xấu đi = to get uglier), it simply means a reduction in intensity or physical property, which can be positive or neutral depending on the context. For example, gầy đi (to get thinner) or nhẹ đi (to get lighter). Note that già đi is the standard phrase for getting older, as aging is viewed as a reduction in youth or vitality. This contrasts with particles like lên (Growing More So) and ra, which indicate increasing or improving states (e.g., khỏe lên = to get healthier; đẹp ra = to get prettier).

Note: Do not confuse this with the imperative Go Ahead And ... which urges an action to start, or with And It Is Gone, which implies an accidental or regrettable loss rather than deliberate disposal. Also, be aware of the highly common colloquial intensifier pattern ... To Death (e.g., mệt chết đi được = tired to death), which is used to exaggerate a feeling rather than indicate a diminishing state.