我不认为你可以在没有javascript的情况下做到这一点。

I don't think you can do this without javascript.

使用javascript，你可以很容易地做到这一点。

With javascript, you could do this easily enough.

我会添加 required 仅在单击复选框后才归属。

I would add the required attribute only after the checkbox is clicked.

事实上，我会将其设为切换件，这样用户就可以取消选中并取消输入。

In fact, I would make this a toggled piece, so that the user can uncheck and unrequire the input.

但是，我不会依赖浏览器执行所需的属性。相反，我会使用一些CSS创建我自己的必需通知（突出显示，动画，显示一些单词）。

However, I would not rely on browser's implementation of the required attribute. Instead, I would create my own required notification using some CSS (highlighting, animation, displaying some words).