Today's tip is on the pronunciation of the letter " t ". （" t "的发音）今天的小贴士是关于字母 " t " 的发音。
Of course the letter " t " is usually pounced " t ". 当然字母 " t " 通常发成 " t "。（编注:原字幕此处有错误）
But you may have noticed that in fluent speech, native speakers sometimes pronounced the " t " as " d ".
但是你可能注意到在流利的口语中，以英语为母语的人有时就会把 " t " 发成 " d "。
That happens when the " t " comes between two voiced sounds. 那通常是 " t " 出现在两个发音的中间。
Do you know what sounds in English are voiced? 你知道在英语里什么音是发音的？（编注:原字幕此处有错误）
Well, there're 15 voiced consonant sounds in English. b, d, g, m, n, ɡ, z, δ, l, r, dз, з, j, w.
在英语中有十五个发音的辅音。
Also, all vowel and diphthong sounds in English are voiced. 同样地，所有英语元音和双元音都是发声的。
So let's look at some examples of words in which the " t " may be pronounced " d ".
所以我们来看下单词中有 " t " 发成 " d " 的例子。

1. "matter".
"matter" is often pronounced "mader" as in "What's the matter?"
"matter" 经常会发成 "madder"如在 "What's the matter?"
2. "atom".
"atom" is often pronounced "adom" as in "The first atom bomb was dropped on Hiroshima."
"atom"通常会发成 "adom"如在"The first atom bomb was dropped on Hiroshima."
3. "twenty".
"twenty" is often pronounced "twendi" as in "That will be twenty dollars, please."
"twenty" 通常会发成"twendi" 如在"That will be twenty dollars, please."
4. "little".
"little" is often pronounced "liddle" as in "He got a little angry."
"little" 通常会发成"liddle" 如在"He got a little angry."
5. "city".
"city" is often pronounced "cidi" as in "Did you grow up in the city or the country?"
"city"通常会发成"cidi"如在"Did you grow up in the city or the country?"
6. "butter".
"butter" is often pronounced "buder" as in "Pass the butter, please."
"butter"通常会发成"buder"如在"Pass the butter, please."

When people speak slowly or emphatically, however, they usually pronounce the " t " like " t ", not like " d ".
当人们慢慢地或强调地说时， 他们通常会把" t " 发成" t "，而不是" d "。
Also, a " t " does not sound like " d " when it comes before a stressed vowel as in "return".
而且是，" t " 不会发成 " d " 当它出现在如 "return" 中一个重音的元音前面。

This has been today's daily tip on learning English. 这就是今天的关于学习英语的小贴士。