I remember my salad days when I was young and inexperienced.

I will finish the project in a few days.

The dog days of summer are always so hot and humid.

In days of yore, people used to travel by horse and carriage.

Back in the days, people used to communicate through letters.

Day after day, she practiced the piano.

The new fashion trend was just a nine days' wonder.

I have been working late for three days in a row.

Days Sales Outstanding is a measure of how long it takes for a company to collect payment from its customers.

I have been working late for five straight days.