1. He goes to the movies once a month.
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In this sentence, what does 'the movies' mean?
It's a casual term meaning he goes to a movie theater to watch movies (films) ...
To understand what "the movies" means in this context, we can break down the sentence: "He goes to the movies once a month."
In general, "the movies" refers to a cinema or a movie theater where people go to watch films on a big screen. It is a common expression for the activity of watching films in a theater.
To confirm the meaning, you can check a reliable English dictionary or use an online search engine. By typing "definition of movies," you will find various definitions and explanations about it. You will see that "movies" generally refers to motion pictures shown in a theater or cinema.