Meaning: A person who watches over swimmers to ensure their safety looked at the people who swim carefully.
Choice of Words: Lifeguard is a noun that refers to a person who watches over swimmers to ensure their safety. Watched is a past tense verb that means to look at something or someone carefully. Swimmers are people who swim.
Alternative Expressions
The lifeguard kept an eye on the swimmers.
Meaning: This sentence means that the lifeguard was watching the swimmers closely to make sure they were safe while they were swimming.
Choice of Words: The lifeguard is a person who keeps watch over swimmers to ensure their safety in the water. Kept an eye on means to watch someone or something closely. Swimmers are people who are swimming in the water.
The lifeguard supervised the swimmers.
Meaning: This sentence means that the lifeguard was watching over the swimmers to make sure they were safe while they were swimming.
Choice of Words: The lifeguard is a person who keeps watch over swimmers to ensure their safety in the water. Supervised means to watch over someone or something and make sure they are safe. Swimmers are people who are swimming in the water.