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1000-hours/sounds-of-american-english/3.5.2-tone.md

@@ -8,13 +8,13 @@ When learning Chinese as a foreign language, one of the biggest hurdles is maste
 
 In contrast, English syllables don't have designated tones, and changes in tone won't alter the meaning of the syllable. Tones in English are usually reflected on the stressed syllable. Sometimes, the last unstressed syllable at the end of a sentence or phrase may carry a tone, which is typically a flat tone.
 
-理论上，重音音节都可以有最常见的三种声调的读法，**平调**、**升调**、**降调**。比如，`→`*big*, `↗`*big*, `↘`*big*，`→`*fact*, `↗`*fact*, `↘`*fact*……
+理论上，**重音音节**都可以有最常见的三种声调的读法，**平调**、**升调**、**降调**。比如，`→`*big*, `↗`*big*, `↘`*big*，`→`*fact*, `↗`*fact*, `↘`*fact*…… 而**非重音音节**只有**轻声**。
 
-In theory, *stressed syllables* can have the three most common tones: *flat*, *rising*, or *falling*. You could say *big* with a flat, rising, or falling tone, `→`*big*, `↗`*big*, `↘`*big*; the same goes for *fact*, `→`*fact*, `↗`*fact*, `↘`*fact*...
+In theory, *stressed syllables* can have the three most common tones: *flat*, *rising*, or *falling*. You could say *big* with a flat, rising, or falling tone, `→`*big*, `↗`*big*, `↘`*big*; the same goes for *fact*, `→`*fact*, `↗`*fact*, `↘`*fact*... In contrast to stressed syllables, *unstressed syllables* are *always* pronounced in a *soft tone*.
 
-偶尔，你也会听到一些人会使用**降升调**，一般是在**双元音**上。比如，`⤻`sure, i`⤻`dea……
+偶尔，你也会听到一些人会使用**降升调**，一般是在**双元音**上。比如，`⤻`sure, i`⤻`dea…… 更多的时候，**降升调**实际上是由两个音节构成的，前一个音节降调，后一个音节升调，比如，*progress* 可以被读成 `↘`*pro*`↗`*gress*.
 
-Occasionally, a *falling-rising* tone is used, typically on *diphthongs*, for instance, *`⤻`sure* or *i`⤻`dea*.
+Occasionally, a *falling-rising* tone is used, typically on *diphthongs*, for instance, *`⤻`sure* or *i`⤻`dea*. More often than not, a *falling-rising* tone is actually made up of two syllables, with the first syllable falling and the second syllable rising. For instance, the word *progress* can be pronounced as `↘`*pro*`↗`*gress*
 
 注意：如果**短元音**的音节用**平调**读出来，会自然而然地有所**拉长**。