mushroom is a compound word because mush and room are words
yes
champiñon
room
No, building is not a compound word.
The contraction (not a compound word) is doesn't.
Upwards is a compound word.
Boletus.
cep
fungus or fungi
There is no compound word.A compound word is a word like bus-stop.Husban is spelt like this husband
Upstairs is a compound word, so it is one word.
Another word for fungus is saprophyte.