用所给词的适当形式填空。 1. When I was reading, I _____ (hear)a noise in the garden. 2. When I _____ (arrive)in Shanghai, it was very hot. 3. This is an _____ (amaze) story. I like it. 4. I _____ (wait) for the bus this time yesterday. 5. Yesterday was Mother's Day, so I _____ (buy)a gift for my mother.