rule re: changing end to "a" if you are female ex: encantada

I am sure this is a common question. I learned that you say encantada if you are female, encantado if you are male. On the second lesson, amy says "necesito" I would have thought that she would make it "necesita". What are the rules on this? thanks!

Hola Lara, Necesito is the first person singular present tense of the verb necesitar, necesita is the second person present tense the formal ud. or él , ella . When Amy says necesito ayuda, it is I need help. Verb endings change with conjugation not gender. Encantado or encantada is an adjective which usually change in number and gender. Studying the written material was a great help when I started and I refer to it often. Buena suerte este curso es maravilloso. Saludos, Rich