Verb conjugation of "derivar" in Spanish

We do not see the spider eating the moth, we only see a yellow spider sitting on a red flower holding a brown moth. But we know what will occur: There will be a cruel and nasty act of the nature.
After placing my luggage there I decided to walk into town and rent a bike. The neighbor of the guest house stopped me on the street and asked me if I was Mike. She told me that she was Luisa.
At around eight in the evening we were back, took a hot shower and met our friends for a fancy dinner. They were leaving the country the next day and we would stay there another three days.