Which is correct?
I never take my iPhone to the gym when I go to _________ because things often go missing from the lockers.
a. work out
Here’s the rule, for work out, set up, log in and so on:
As a verb, use two words: You work out. You set something up. You log in. These are known as phrasal verbs.
As a noun or adjective, make it one word: You do a workout. You plan a setup. You complete a login procedure.
June Casagrande explains more about compound words and phrasal verbs.
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