The opposite of happy is ...
sad
The opposite of young is ...
old
The opposite of far is ...
near
The opposite of short is ...
tall/long
The opposite of good is ...
bad
The opposite of noisy is ...
silent
The opposite of heavy is ...
light
The opposite of cold is ...
hot
The opposite of big is ...
small
The opposite of fast is ...
slow
The opposite of pretty is ...
ugly
The opposite of up is ...
down