Sun Tang is a thirteen-year-old girl and she studies in a big school．She is in Mr Yang's class．Mr Yang teaches Chinese and he thinks students should keep a diary(写日记)．He believes it's a good way to learn Chinese．Sun Tang is good at maths，but she isn't interested in keeping a diary．Last Friday,Mr Yangintroduceda book about writing to Sun Tang．Yesterday,she took a bus to the shop and bought the book．
Wu Kai is twelve years old and studies in a small school．He is in Miss Ling's class and he is the PE monitor．Wu Kai has a strong body and plays basketball well．He also likes other sports，such as swimming．But his mother worries about him and always asks him not to swim alone．So Wu Kai often swims with his father．It's hot today．Wu Kai wants to swim after school.
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