I speak English.
I speak to English.
一つ目が正解だと思いますが、toを付けない理由を教えてください。
また、会話の中ではtoを付けてしまっても成り立ちますか？

See a translation

@hiro163

I speak English. ✔️👏
I speak to English. ❌❌❌❌❌😬🤯

The English language is not a person. You cannot speak TO English.

You can speak to a person. You can speak to a crowd of people. You can speak to your mother-in-law, who is also a person. You can speak to your dog, if you think that he understands you, or even if he doesn’t. You can speak to the wall – as long as you understand that the wall cannot understand you. You can speak to a recording device – although we would usually say that you speak INTO a recording device, since the sound goes inside the machine and stays there.