When do you use ‘ser’ and ‘estar’? – Easy Learning Grammar Spanish In Spanish there are two irregular verbs, ser and estar, that both mean to be, although they are used very differently. In the present simple tense, they follow the patterns shown below. To be or to be. … Sigue leyendo A Guide to the Differences Between the Spanish Verbs Ser and Estar by Prof. MMag. Karin Silvina Hiebaum