A noun (or a collective noun) functions as the subject of a sentence or a clause, and as the object of a verb or a preposition.
Examples:
The noun crew is functioning as the collective noun in 'a crew of rowers'.
The noun 'crew' is a collective noun for: a crew of barbers a crew of laborers a crew of pilots a crew of rowers a crew of sailors a crew of firemen or rescue workers.
The collective noun 'crew' is singular, one crew. The correct verb is 'The crew prepares...'.
crew
The collective noun for sailors is a crew.
Collective nouns for miners are a crew or a shift.
The collective noun for pilots is a crew of pilots.
The collective nouns for the noun 'workers' are:a crew of workersa staff of workers
Since workmen are people, you use an appropriate collective for the context. The most common is crew, but you could also use shift, collective, company, team, etc.
Example sentences for the collective noun 'crew':A crew of laborers cleared the debris that blocked the road.The crew of sailors stood at attention for the captain's review.Coffee will be served to the crew of pilots soon after takeoff.A crew of firemen have blocked off the street of the fire.I'm trying out for a position on the crew of rowers.The crew of rescue workers airlifted the victims to safety.
The standard collective noun is a crew of workmen.
The collective name for a group of sailors are called a crew