Past Simple or the Past Continuous. Пліііз помогите

Last summer, we (sail) off the coast of New Zealand when we (see) a group of dolphins. They (jump) in the water. We (stop) and I (dive) into the water to take some photos of the dolphins. I (take) photos when one of the dolphins (swim) towards me and (push) me towards the boat. The other dolphins (watch) us all the time. They (not play) any more. I (look) around and (see) a huge shark. I (get) out of the water very quickly. When I (get) onto the boat, the dolphins (disappear) at once. They saved my life.