参考例文：
Dear Mrs Brown，We are so glad that you're coming to join us on Saturday. Here is how you can find us. We'll have our gathering party in the Central Park. Maybe you've been there，haven't you？
Go straight on when you get out of the school gate and come to the street. Then turn right at the second crossing and you'll find a hospital. Just opposite it is a No. 7 bus stop. Take a bus and get off at the fourth stop. Central Park is just in front of it. We'll have our gathering party in a boat on the lake. What a funny thing！ Do come on time. We'll wait for you at the park gate
