在英语作文中描述“家有姐妹”时，你可以按照以下结构来写：

介绍家庭成员：

首先，提到你的家庭成员，包括你和你的姐妹。

描述关系：

然后，描述你和你姐妹之间的关系，比如她是你的妹妹，你们一起长大的经历等。

分享感受：

接着，分享你和你姐妹之间的感情，以及她在你生活中的重要性。

总结：

最后，总结家庭生活的美好和姐妹之间的深厚友谊。

Title: My Family

I have a family of three members, which includes my father, my mother, and me. Among them, my younger sister is a very important part of my life.

Growing up with my sister was an unforgettable experience. We shared countless moments of joy and laughter, as well as some minor disputes and misunderstandings. However, these experiences only strengthened our bond and made us closer.

My sister is not only my younger sister but also my best friend. She is always there to lend a listening ear when I need one, and she is always ready to offer help and support whenever I am in trouble. Whether it's talking about our daily lives, sharing our dreams and aspirations, or simply venting our frustrations, she is always my go-to person.

Having a sister has brought so much joy and meaning to my life. She has taught me the importance of family, friendship, and love. I am grateful for having her in my life, and I cherish every moment we spend together.

In conclusion, my family, especially my sister, has made a profound impact on me. They are the foundation of my life, and I am grateful for their love and support.