We do that when the sound before is unvoiced.

当其前面的音为不发音时，我们会这样做。

And a 'th' at the end of a word is usually unvoiced.

单词末尾的“th”音一般也都是清辅音。

So the 'th' at the start of content words is usually unvoiced.

所以实义词之前的“th”一般都是清辅音。

Mainly as a girl, I learned, as a girl, that anger is an emotion better left entirely unvoiced.

主要是作为一个女孩，我了解到， 作为一个女孩，愤怒是一种情感，最好将它置之不顾。

There's the voiced TH and the unvoiced TH.

有浊音 TH 和清音 TH。

Unvoiced consonant sounds are made by air pushing through your mouth.

清辅音是空气通过你的嘴巴进行发音的。

An unvoiced consonant is one where there's no vibration here.

不发音的辅音是指这里没有振动的辅音。

These sentences have both the voiced and unvoiced TH.

这些句子包含 TH 的两个发音。

It happens in the past tense when verbs end with an unvoiced sound.

这发生在过去式中动词以清音结尾的情况。

The voiced TH sound is almost exactly the same as the unvoiced TH sound.

浊 TH 音和轻 TH 音几乎完全一样。

This is called the unvoiced TH sound.

这被称为不发音的 TH 音。

So a 'th' at the beginning of content words is usually an unvoiced 'th' sound.

在实义词前的“th”通常都是清辅音。

Now as I mentioned, there are two 'th' sounds, a voiced sound and an unvoiced sound.

正如我之前所说，“th”有两种发音，一种是浊音，一种是清音。

It's unvoiced because there's no vibration here.

它是无声的，因为这里没有振动。

So this is the unvoiced 'th' sound.

这就是清辅音“th”。

With an unvoiced TH, the tongue tip does have to come through the teeth for this. Method.

对于无声的 TH 来说，舌尖必须穿过牙齿才能做到这一点。

Now this 'dith' end in an unvoiced th sound, tongue tip 'dith' come through the teeth for that, 'Meredith'.

现在这个 dith 以不发音的 th 音结尾，发音时舌尖从牙齿中间露出来，Meredith。

So that is an unvoiced sound.

所以那是个清音。

So when should you use the voiced or the unvoiced sound?

那什么时候该使用清辅音，什么时候该使用浊辅音呢？

It's got that unvoiced TH at the beginning.

一开始就是清音。