Definition

1. Demonstrative pronoun: A demonstrative pronoun used to indicate an object's length by comparing it to a length that has been previously mentioned, shown, or is understood in the context. It means "that long" or "of that length".

Usage Instructions

• "Bây dai" is used exclusively to describe the length of an object. It cannot be used for other dimensions like width or height.
• It functions as a predicate or a post-nominal modifier, following the noun it describes.
• It always refers back to a specific length that has been established in the conversation or situation. It is the equivalent of pointing and saying, "Like this long."
• It is a colloquial term, commonly used in spoken Vietnamese, particularly in the Southern dialect.

Usage Examples

• As a post-nominal modifier:

  • Tôi cần một sợi dây bây dai. (I need a rope that long.)
  • Nó có cây thước bây dai không? (Do you have a ruler that long?)

• As a predicate (with the subject being the length):

  • Cây gậy phải dài bây dai. (The stick must be that long.)
  • Con đường chỉ bây dai thôi. (The road is only that long.)

Advanced Usage

• Implied Comparison: The specific length is often demonstrated physically (e.g., by holding hands apart) or referenced from a prior statement.
  • Cắt cho tôi một mảnh vải. Ngắn thôi, cỡ bây dai. (Cut a piece of fabric for me. Short, just about this long.) [Speaker likely gestures.]

Variants and Related Words

• Bấy dai: A less common variant with the same meaning.
• Bây giờ (now): A phonetically similar but completely unrelated word regarding time.
• Dài (long): The adjective for "long". "Bây dai" incorporates this word to specify "that long".
• Cỡ này (this size): A more general term for size/dimensions, not specific to length.

Synonyms

• Dài cỡ đó: Of/about that length. (A more descriptive synonym.)
• Dài như vậy: Long like that. (A more formal equivalent.)

Antonyms

• Bây ngắn: That short. (The direct antonym, following the same grammatical structure.)

Notes on Different Meanings

• "Bây dai" has only one primary meaning: to indicate a specific length ("that long"). It does not have other metaphorical or idiomatic meanings.
• It is part of a demonstrative pattern in Southern Vietnamese: bây + adjective (e.g., bây cao = that tall, bây lớn = that big).

1. That long
   • Một cái gậy bây dai
     A stick that long