A. A while + was/were + INC + Form 2 verb

A while ago, I was sleeping when my phone rang.

I was reading a book a while ago when I heard a loud noise.

A while ago, we were walking in the park when it suddenly started raining.

I was working on my project a while ago when my computer suddenly shut down.

A while ago, I was watching TV when the power went out.

B. Form 2 verb + while I was / were + ING

Singing while I was cooking made the time pass quickly.

I was jogging while my friend was cycling around the park.

While I was studying for my exam, my brother was playing video games.

My mom was washing the dishes while I was sweeping the floor.

While I was walking home from school, I saw a dog running in the street.

C. When + Form 2 verb + was / were + ING

When I arrived at the airport, my sister was waiting for me.

When I woke up this morning, the sun was shining brightly.

When we entered the room, the baby was sleeping soundly.

When I opened the door, my cat was meowing loudly.

When I checked my email, my boss was already asking for the report.

D. was / were + ING + When + form verb

The kids were playing outside when it started to rain heavily.

My phone was charging when it suddenly stopped working.

My sister was cooking when she accidentally burned the food.

I was walking to the store when I saw a car accident.

The guests were already eating when we arrived at the party.