When Pigs Fly... from Around the World

Kad na vrbi rodi grožđe
When grapes rippen on the willow
除非太陽從西邊出來 [除非太阳从西边出来] (chúfēi tàiyáng cóng xībiān chūlái)
Unless the sun would rise from the West
Kad na vrbi rodi grožđe
When grapes rippen the on willow
Na sveto nigdarjevo
On St. Nobody's day
Až na svatého Dyndy / Na svatého Dyndy
On the St. Elsewhen's day
'Dyndy' is a non-existent name in Czech, rhyming with the Czech word 'jindy', meaning some other time.
Når helvede fryser til is
When hell freezes over
Når der er to torsdage i en uge
When there's two Thursdays in a week
Wanneer Pasen en Pinksteren op één dag vallen
When Easter and Whitsun fall on the same day
Met sint-juttemis
With St. Juttemis
When pigs fly / and pigs might fly.
When hell freezes over.
On a cold day in hell
Not in a month of Sundays.

Finnish
Wenn Ostern und Pfingsten auf einen Tag fallen
When Easter and Whistun fall on the same day
Am Sankt Nimmerleinstag / an Sankt Nimmerlein
On Saint Never's day / on Saint Never
Wenn die Hölle zufriert
When Hell freezes over
Wenn es im Sommer schneit
When it snows in summer
sooraj pashchim se ugega
When the sun will rise in the west
Majd ha piros hó esik
When it's snowing red snowflakes
Majd ha cigánygyerekek potyognak az égből
When gipsy children are streaming from the sky
Majd ha a pokol befagy
When Hell freezes over
Alle calende greche
By the Greek calendar
Quando voleranno gli asini
When donkeys will fly
Quando Pasqua viene a maggio
When Easter falls in May
L'anno del mai / L'anno del mai e il mese del poi
The year of never and the month of then
Nella settimana dei due giovedì
In the week with two thursdays
Quanno pisceno le galline
When hens piss (Roman dialect)
Ad kalendas Graecas
on the Greek Kalends - unlike the Roman calendar, Kalends did not feature in the Greek calendar, so this phrase is roughly equivalent to "at British Thanksgiving" (Thanksgiving is not celebrated in the UK).
Kad pūcei aste ziedēs
When the owl's tail blossoms
Kad slotaskātam lapas plauks
When the broomstick's leaves open
Wann Päischten op Neijôrsdag fällt
When Whistun and New Year's Day fall on the same day
Кога врбата ќе роди грозје (Koga vrbata ke rodi grozye)
When grapes will grow on willows
На куково лето (Na kukovo leto)
In the year of the cuckoo
Kakka malannu parakkum
The crow will fly upside down
Når griser flyr
When pigs fly
Når det snør i helvete
When it's snowing in hell
Na Święty Nigdy
on Saint Never's Day
Kiedy mi kaktus na ręku wyrośnie
When the cactus will grow on my hand
Quando a vaca tussa / quando a vaca tossir
When the cow coughs
No Dia de São Nunca
On Saint Never's day
La Paştele cailor şi la nunta vacilor
At Easter of the horses and at the wedding of the cows
Когда рак на горе свистнет (Kogda rak na gore svisnet)
When the crayfish on the hill whistles
Kad na vrbi rodi grožđe
When grapes grow on willows
Ob svetem nikoli
On Saint Never's Day
Cuando las ranas críen pelo
When frogs grow hair
El día del arquero
Goalkeeper's day
När grisar flyger
When pigs fly
När helvetet fryser till is
When hell freezes over
Pagputi ng uwak
When the crow turns white
Pag-itim ng tagak
When the heron turns black
ตอนเซเว่นปิด (ton sē wēn pit)
when the 7-11 is closed
ชาติหน้า (chāt nha)
next lifetime
Balık ağaca/kavağa çıkınca
When fish climb trees/poplar trees
коли рак на горі свисне (koly rak na gori svisne)
when the crayfish on the hill whistles
коли воша пчихне (koly voša pčyxne)
when louse will sneeze
(cho đến) Tết Marốc
(until a) Moroccan Tet (Tet is Vietnamese New Year)
Pan fydd moch yn hedfan
When pigs fly
Pan fydd uffern yn rhew drosodd
When hell freezes over
When pigs fly, you'll find them here.
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