Hello. I can help you, but I can't see the lesson section page 3. I'm Cuban and a Spanish teacher. So, if you give me more details, I can definitely help you.
Los señores García llegaron tarde a la fiesta.
You must use a definite article (<u>masculine</u> and <u>plural</u> to agree with the accompanying noun) is "los".
It is a definite article because they are <u>exact</u> gentlemen (Los Señores García).
<h3><em><u>MissSpanish</u></em></h3>