妈妈正在做饭,这时有人敲门.用英语怎么说

Mum was cooking when someone knocked at the door.

There was a konck on the door while Mum was cooking .

there is someone knocking at the door when mother was cooking.
someone knocking at the door while mother was cooking

Mom is cooking, when someone knocks on the door

Mum was cooking when there was a knock on the door.

Mother was cooking when someone knocked at the door.

Mom cooked when someone was knocking at the door.
Mom was cooking when someone knocked at the door.

Mom was cooking when someone knocked the door.