Colors & shapes

red	rojo / roja	circle	el círculo
pink	rosado / rosada	square	el cuadrado
orange	anaranjado / anaranjada	rectangle	el rectángulo
yellow	amarillo / amarilla	triangle	el triángulo
green	verde	oval	el óvalo
blue	azul	cube	el cubo
light blue	celeste	sphere	la esfera
purple	morado / morada	cylinder	el cilindro
violet	violeta	cone	el cono
brown	marrón	octagon	el octágono
black	negro / negra	box	la caja
gray	gris	pyramid	la pirámide
white	blanco / blanca
golden	dorado / dorada	dark	oscuro / oscura
silver	plateado / plateada	light	claro / clara

All adjectives in Spanish are placed after the noun that they describe and they agree in gender (masculine or feminine) and number (singular or plural) with the noun. Notice that some colors do not change for gender (marrón) or number (gris). To change an adjective to the feminine form, you usually just change the final -o to -a. To make an adjective plural, simply add an -s.

a red house = una casa roja