Complete the sentences with the correct form of the verbs. Use Past Simple or Past Countinuous

Amy was sleeping when Sam went out to buy some flowers.

I ran towards the train station when the train arrived.

Helen and Ben broke the window of the candy shop while they were playing with a ball in the garden.

I dropped my keys on the floor while I was looking for the wallet.

I saw a beautiful blue bird on the tree when I was waiting for my friend.