Final answer:
The pronouns 'te', 'los', 'me', 'la', 'nos', and 'lo' refer to specific people or groups of people in the sentences.
Step-by-step explanation:
1. Te llamé anoche.
The pronoun 'te' refers to the person being spoken to. It can be translated as 'you' in English.
2. Quiero invitarlos a la fiesta.
The pronoun 'los' refers to multiple people being invited. It can be translated as 'them' in English.
3. ¿Por qué no me saludaste?
The pronoun 'me' refers to the speaker. It can be translated as 'me' in English.
4. Ya la felicité.
The pronoun 'la' refers to a female person who has already been congratulated. It can be translated as 'her' in English.
5. Gracias por ayudarnos.
The pronoun 'nos' refers to the group of people being thanked. It can be translated as 'us' in English.
6. Nosotros lo visitamos la semana pasada.
The pronoun 'lo' refers to a male person who was visited. It can be translated as 'him' in English.
Learn more about Understanding pronouns in Spanish