Our dog has a bald patch on its leg.

我们的狗腿上脱了一片毛。

The dog has a bald patch on its back.

这条狗的背上有一块地方不长毛。

Our dog has a bald patch (ie a patch with no hair) on its leg.

我们的狗的腿上秃了一块。

When I comb my hair, I'm confronted by an ever-bigger bald patch.

在梳理头发时，我将面对愈加光秃的头皮。

He's not that great, you know. I saw the beginnings of a bald patch .

他没那么英俊，你知道，我看到他有点秃头了。