Use e instead of y when a word begins with
i or hi (but not hie)
Use u instead of o when the word begins with
O or ho
Padre - hijo
E
Fuego-hielo
Y
Fernando-Isabel
E
Gracia-ironía
e
Plato-oro
U
Uno-otro
U
Oro-plata
O
But, however
Pero
But on the contrary, but rather
Sino
Used to introduce a clause (which contains a conjugated verb)
Sino que