Idioms of Improbability|猪乸會上樹

有一種修辭手法用黎誇張地形容一件事永遠冇可能發生，或者極微機會發生，英文叫

adynaton: A form of hyperbole that uses exaggeration so magnified as to express impossibility.

（有冇人識中文點叫？）

Idiom	Literal Translation	Notes
猪乸會上樹	"The female pig will climb a tree"	Freakishly similar to the English idiom "When pigs fly"! (Frequently used with a preceding [type of person] 靠得住...)
太陽由西邊出黎	"The sun will rise from the West"	Also used in Mandarin
咁我係李嘉誠個仔	(If [improbable thing is true], then “I am the son of Li Ka Shing!”)	Li Ka Shing is one of the richest persons in HK. Being his son (and thus being able to inherit his fortunes) is impossible
俾個港督你做	“I’ll give you the position of Governor of Hong Kong!”	I don’t seem to have heard 俾個特首你做 since 1997. Maybe no one wants to be the Chief Executive of HKSAR?
批個頭落嚟畀你當凳坐	“I’ll cut off my own head and let you sit on it”	When you are so confident betting against something that you would bet your head off, so to speak
(如果… )我就唔姓X	“Then my surname won’t be X [X= your real surname]”	Surnames (last names) bear the family pride. You are so confident about the improbability of something that you would put your surname on the table.

仲有冇其他大家聽過既表達方法？

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