仔细考虑用英语怎么说是 "think carefully about how to say something in English". 这句话的来源是根据其中的词语而推断出来的。例如，"仔细"可以用英语表达为 "carefully"，"考虑"可以用 "think about" 表示，"用英语怎么说" 可以用 "how to say something in English" 来表达。因此，把这些词组合在一起就能得到 "think carefully about how to say something in English" 这句话了。

例句：

I always think carefully about how to say something in English before I speak. 我在说话之前总是仔细考虑用英语怎么说。

It's important to think carefully about how to say something in English so that you can communicate effectively. 仔细考虑用英语怎么说对于有效沟通很重要。

When you are learning a new language, it's helpful to think carefully about how to say something in that language. 当你在学习一门新语言时，仔细考虑用这门语言怎么说是非常有帮助的。