This is a fundamental problem.

He challenged this exam with the determination of staking everything.

This train is crowded every morning.

The air conditioner has broken down, so it needs to be repaired.

Good communication is the key to success.

He spent his money as quickly as 'a duck comes bearing green onions', which means a fool and his money are soon parted.

Since he is always laughing, it can be said that 'fortune comes in by a merry gate'.

This product is designed for consumers.

He is troubled by hypochondria.

Every morning, I spread confiture on bread and eat it.