Hello, boys and girls! My name is Zhang Hanyun, and my English name is Selina Zhang. Kristy Zhang's Chinese name is also Zhang Hanyun. She is a singer. But I'm a clerk  at Mr. Cool's Clothes Store. We have shorts in black and white for $3. We have shirts in blue, black and white. The blue shirts are $7. The black shirts are also $7. The white shirts are on sale for $4. For boys, we have white socks. A pair of white socks is only $1. We only have black shoes. We sell black shoes for only $18. Come and see for yourself at Mr. Cool's Clothes Store. You have $21, and you can buy   _   pairs of shorts.
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