Days of the Week

lunes (m) Monday
martes (m) Tuesday
miércoles (m) Wednesday
jueves (m) Thursday
viernes (m) Friday
sábado (m) Saturday
domingo (m) Sunday
alberca (f) swimming pool
circular circulate
contaminación (f) pollution
descancar to rest
día de trabajo (m) workday
evitar to avoid
fin de semana (m) weekend
gobierno (m) government
grave (adj) serious
misa (f) mass
números nones (m) odd numbers
números pares (m) even numbers
placa (f) license plate
subir to rise

Odio los lunes porque tengo que trabajar. I hate Mondays because I have to work.
Los lunes, miércoles y viernes voy a nadar a la alberca de la escuela. On Mondays, Wednesdays, and Fridays, I go to swim at the school pool.
Los sábados voy a bailar con mi novia. On Saturdays I go dancing with my girlfriend.
Los domingos son para ir a misa. Sundays are for going to mass.
Gracias a Dios es viernes. Thank God it's Friday.
Tengo muchos planes para este fin de semana. I have many plans for this weekend.
Voy al gimnasio todos los días entre semana. I go to the gym every weekday.
Vamos a salir de vacaciones el próximo viernes. We're going on vacation this Friday.

The days of the week, and related words are used differently between Spanish and English. Notice first of all that they are not capitalized in Spanish. In English we use the preposition "on" with the days of the week, but Spanish speakers use the definite article "the." For example, "Siempre estoy en casa los martes." (I am always home on Tuesdays.) Note, also, that with the ver SER, there is no article when using the days of the week, e.g., "Hoy es miércoles." (Today is Wednesday.)

lunes Monday
martes Tuesday
miércoles Wednesday
jueves Thursday
viernes Friday
sábado Saturday
domingo Sunday

Examples:
Hoy es lunes. Today is Monday.
Mañana es viernes. Tomorrow is Friday.
Carlos está en Austin los lunes. Carlos is in Austin on Mondays.