There are two types of subjects in English: nouns and pronouns.

PRONOUN
When an English sentence uses a pronoun as a subject (I, you (s.), he, she, it, we, you (pl.), and they), it is straightforward that the Latin verb ending must reflect that (-o, -s, -t, -mus, -tis, -nt).

But what about when there is not a pronoun subject in the English sentence? Does that mean the Latin verb does not have an ending? And if it does need an ending, what ending?

NOUN
When an English sentence uses a noun (or more than one noun) as a subject, the Latin verb must have a 3rd person ending that reflects whether the subject is singular or plural. Singular noun subjects require a 3rd person singular ending (-t). Plural noun subjects and compound subjects require a 3rd person plural ending (-nt).

The farmer is looking at the islands. [Since the subject (farmer) is singular, the verb must end with -t.]
Agricola insulas spectat.
Think about it. "The farmer is looking at the islands. HE is looking at the islands."

The women are in the farmhouse. [Since the subject (women) is plural, the verb must end with -nt.]
Feminae in villa sunt.
Think about it. "The women are in the farmhouse. THEY are in the farmhouse."