题目内容：
根据下面内容，回答题：Kate : Hello ! 56
Mrs. Read:I'm sorry. Ann isn't here right now. 57
Kate : This is Kate.
Mrs. Read:She isn't back yet. 58
Kate :That's very kind of you. I'm calling to ask her if she is free tomorrow. It's March 12th, Tree Planting Day tomorrow. 59
Mrs. Read:I think she'll be very glad to join you.
Kate:We'll meet at the school gate at 7: 00. 60
Mrs. Read:OK. I'll let her know.
Kate : Many thanks. Goodbye.
Mrs. Read : Goodbye.Goodbye.
第56题应填( )
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