Greetings, Do - Does - they are used in Simple Present Tense. Example- I do not know about her. -She does not speak English. Do you study? Is -Am- Are- they are helping verbs used in Present defining/introductory sentences. Example- I am a teacher. - You are a student. Hope it helps ! Regards, Mantra Deepika

Hello Eli, I am not sure what you mean with the question. As i read it it seems as if you think that is and do come from the same word? That is not the case. "Is" comes from "(to )be" where "do" is the base form of "(to) do". In conjugation they look like this: I am you are he/she/it is we/you(plural)/ they are I do you do he/she/it does we/ you(plural)/ they do