Crews and cruise are homophones and easily confused words. The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway. Similarly, autocorrect on mobile phones might suggest one word instead of the other, it would be easy to do since both words start with “c-r.”
Crews is a plural form of the noun crew. Crews are people who work on boats, planes, or other vessels.
Cruise is a noun, meaning a slow journey, typically on a boat. But cars also have “cruise control”, a setting meaning the speed is maintained at a steady pace with no noticeable acceleration.
The following sentence uses both words correctly:
Cassie’s dream after high school was to join one of the crews on a local cruise ship, ultimately becoming a bartender so she could talk to lots of people and hear their stories.