[解析]
(1)、C 18.A 19.A 20.B
【原文】M:My dad has always told me to help others.Last week I was walking back home and I passed by an old lady who seemed to be in trouble.I asked if she was OK.She explained that she was sick and had to struggle to walk with her shopping bags.I offered to carry her things but she refused because she didn't want to give me any trouble.I told her that it didn't matter and her home was near my home.It was a white lie.She talked with me and introduced herself.I,in turn,told her my name.She asked if I knew Ray Robert.I was shocked and said, "Yes,that was my dad." It turned out that this lady was my dad's neighbor who had looked after my dad when my grandmother died in 1980.My dad had often spoken of her but I had never met her as she had moved away.When I got home and told my dad about the incident,it made him cry.I'm glad that my small act of kindness ended in a chance meeting that meant so much to us.