写关于小猫或小狗的英语作文时，可以按照以下结构来组织内容：

开头

简单介绍宠物种类（猫或狗）。

表达自己对宠物的喜爱之情。

描述宠物的外貌特征

名字。

性别。

颜色。

主要特征（如眼睛、耳朵、鼻子、毛色等）。

描述宠物的性格和行为

性格特点（如可爱、友好、聪明等）。

常见行为（如玩耍、吃东西、睡觉等）。

描述与宠物的互动

和宠物一起做的有趣事情。

照顾宠物的经历。

结尾

总结对宠物的感情。

表达对宠物的喜爱和感激之情。

I have a lovely dog.

Its name is Bobo. She is a female dog. She comes from Beijing. I like her very much. She has two big ears and two bright eyes. Her hair is white. She is very cute and friendly. I often take her for walks in the park. She enjoys playing with other dogs and eating ice cream. She is my best friend.

关于小猫的英语作文示例：

My kitten

My kitten is named Mimi. She is very cute. She has big eyes and grey and white fur. She likes to sing and jump. I love her very much. She is very playful and curious. I often play with her and feed her. She is my little companion.

通过以上结构和示例，你可以根据自己的喜好和经历来撰写关于小猫或小狗的英语作文。记得使用生动的描述和具体的细节，这样可以使作文更加有趣和生动。