the comma is missing between beach and while
Maria lay on the beach while her brother splashed in the waves.
Let's begin with the sentence alone, "Maria went with her boyfriend." Maria and boyfriend are both nouns. However, Maria is the subject of the sentence, and went is the verb.
Yes, "Maria is beautiful" is a sentence because it has a subject and a verb.
The antecedent of their in this sentence is "Ana or Maria."
Bernardo
He doesn't have a brother, he has a sister, Maria Isabel.
In the musical West Side Story, Bernardo was Maria's brother.
Maria has two younger siblings; a brother named Bill and a sister Janny.
Maria had talked.
Maria lives with her brother Billy sister Janny and her parents of course
Maria Tallchief has two siblings. A younger sister and an older brother.
Shadow and Maria are not biologically related, however it's assumed that Shadow and Maria shared a brother-sister bond.
His father's name was Josef, his mother Maria, a sister Maria and a brother Georg.