He bought a new clock.

In organic chemistry, azulene is known as a special compound.

His plan fell through.

Leap day is a special day that only comes once every four years.

In a leap year, there are 366 days.

He spent a long time in a sickbed.

His father died of illness.

Around the end of summer, I feel the end of summer.

He solved the problem in 100 seconds.

The lake spread boundlessly, seeming to continue forever.