Buen, bueno, mal, malo
is there anyway to know when to use buen and when to use bueno, likewise, mal and malo in the masquline? I thought that maybe the O's were droped when following a noun starting with another vowel, but this seems to be specious reasoning.
Buen is the form used before a singular masculine noun.
1). ¡Que tengas buen viaje! - have a good journey!
2). Sería bueno que hablaras con ella - It would be a good idea if you spoke to her.
Malo/mal is similar to bueno/buen in this way but you might want to take notice of the fact that the word mal is also used as an adverb - poorly (see below) and as a noun - evil
Don't get the adjective "malo" confused with the adverb "mal"
La comida es mala [adjective] porque cocina muy mal [adverb] - The food is poor/bad because she cooks very poorly.
malo/mala - adj. of poor quality
mal - adv. poorly (done/made etc)
Therefore can you say that at school you used to do badly in mathematics?
"Hacía mal en matemáticas en la escuela" (I did bad in mathematics/I didn't do well in mathematics)
Bien = adverb bueno = adj