when

He left home when he was twenty-three.

He left home when he was twenty-three.

I really miss my family when I'm away from home.

I really miss my family when I'm away from home.

Please close the door when you leave.

Please close the door when you leave.

Many students experience difficulty when learning a new language.

Many students experience difficulty when learning a new language.

Please close the door when you leave the room.

Please close the door when you leave the room.

You risk your job when you ignore a safety rule.

You risk your job when you ignore a safety rule.

You must always tell the truth, even when it's difficult.

You must always tell the truth, even when it's difficult.

I learned to ride a bike when I was six.

I learned to ride a bike when I was six.

She sighed with relief when she heard the news.

She sighed with relief when she heard the news.