coastguard:
(plural: ‘coastguards‘; pronunciation: the letters ‘c’ is said with a ‘k’ sound as in “king”)

a coastguard or coastguardsman patrolling
a person in the Navy or the police whose job is to watch for ships in danger and prevent unlawful (smuggling) activities at sea and in coastal areas; a coastguardsman (with plural form ‘coastguardsmen’ and also as two words ‘coast guardsman‘)
(‘Coastguard’ is also used for the entire service/force of the military division that looks after the traffic of ships and shipping activities; saves lives at sea and prevents smuggling and illegal activities, etc. in coastal waters.),

coastguards training
Jonathan is a coastguard/a coastguardsman, and as a coastguardsman he knows how to swim, how to handle weapons and how to save people from drowning.
Most countries in the world have trained coastguard service and every day coastguards or coastguradsmen and costguardswomen save hundreds of people from drowning all over the coastal areas of the world.
One of the most difficult tasks of a coastguard or coastguardsmen and women is to prevent smugglers from entering their countries via their coastal areas, and in addition, to protect ships and ships’ crew and passengers from the recent phenomenon of pirates.
