It’s no secret that Spanish has a lot of endings, way more to memorize than in English. Thankfully there are some tricks to make learning some words a little easier. Note that this is different than learning verb endings which your teacher will help you grasp, memorize, and practice. Here, we can simply follow some patterns of similarity between English and Spanish.
-ly :: -mente
With common adverbs, if it ends in -ly in English, replace it for -mente.
e.g.: Rapidly/rapidamente, profusely/profusamente, horribly/horriblemente, terribly/terriblemente
-tion :: -ción
With words ending in –tion, replace the ending for –ción
e.g.: Relation/relación, imagination/imaginación, accommodation/accomadación, foundation/fundación, information/información
-ity :: -dad
In words ending in –ity, replace it for -dad
e.g.: Quality/calidad, quantity/cantidad, city/ciudad, inferiority/inferioridad, spirituality/espiritualidad, negativity/negatividad
This is a general trick to help when you are stuck but it does not apply to all words in these forms. Nothing replaces actually studying to memorize words and learning hard and fast rules but I have definitely used these tricks to help out when I am speaking and just can’t think of the word!
Esto funciona de Español a Inglés también! Cuando tengas dudas, simplemente reemplaza palabras que terminan con -mente a -ly, -ción a -tion, y -dad a -ity.