一个人不想结婚的英文句子可以是：

1. I don't want to get married.

2. I don't want to get married because I don't want to take on any responsibilities.

3. Not marry.

这些句子都表达了不想结婚的意愿。第一句是直接表达不想结婚，第二句解释了不想结婚的原因是不想承担任何责任，第三句则是一个简洁的否定表达。