The lazy dog slept all day long.
Meaning: This sentence tells us that the dog is very lazy and doesn't like to do anything but sleep.
Choice of Words: Lazy means lacking energy or motivation. Slept is the past tense of sleep, which means to be in a state of rest. All means the entire amount or quantity. Day refers to a 24-hour period. Long means having a great length or duration. When you put them together, "The lazy dog slept all day long" describes a dog that spends most of its time sleeping.
Alternative Expressions
Related Expressions