1. A Pedro le gusta ir de compras en el
Centro comercial
2. A mi me gusta Nadar en la Piscina
3. Las chicas y Yo bebemos Refrescos
Hola, John. Sí, ayudo en el restaurante de mi madre los domingos y los lunes.
¿No trabajas los martes?
B) they shake each other's hand
The verb in this sentence,"se dan", comes from "darse", which is a reciprocal verb (verbo recíproco) and these verbs always talk about something that the speakers are mutually doing, so the other options wouldn't be correct because: 1) They aren't referring to the 3rd person of plural, 2) They aren't doing a reciprocated action.
Hope this helped you :)
Grandes, grande one of those 2
