Using the past continuous with the past tense. Add another clause using a past tenses verb.
Example: They were solving some Math problems.
They were solving some Math problems when the teacher came.
He was speaking in English and Spanish

I was taking John with me

I was walking through the street

They were trying their best to complete the project

Tom was wearing black pants

She was laughing at me

They were leaving me alone

I was learning Karate

They were kissing each other on the rooftop

She was hugging me so tight