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1000-hours/sounds-of-american-english/2.1.5-ə.md

@@ -18,9 +18,13 @@ The rhotacized `ɚ` and `ɝː` sounds, can be produced in two different ways. Mo
 
 Since the tongue's movements are invisible during speech, it's difficult for learners to guess the second method, which involves lifting the back part of the tongue, and allowing the sides of the tongue to touch the back teeth. The center of the tongue's rear is slightly lowered, creating a groove for the air to pass through and generate the sound.
 
+另外，辅音 `ʃ/ʒ`、`tʃ/dʒ` 在发音的时候，舌尾也是同样的位置。
+
+Moreover, when pronouncing the consonants `ʃ/ʒ` ([2.2.8](2.2.8-ʃʒ)) and `tʃ/dʒ` ([2.2.10](2.2.10-tʃdʒ)), the position of the back part of the tongue is the same.
+
 值得注意的是，美式英语的 `ɚ` 和 `ɝː` 在发音时，**舌尖从不接触牙或者龈嵴**。
 
-It should be noted, in American English pronunciation, the tongue tip *never* touches the teeth or the alveolar ridge when making the rhotacized `ɚ` or `ɝː` sound.
+It should be noted, in American English pronunciation, the tongue tip *never* touches the teeth or the *alveolar ridge* when making the rhotacized `ɚ` or `ɝː` sound.
 
 注意，在连贯的自然语音中，很多非重音音节的元音，都有被简化成 `ə`（*schwa*）的倾向，尤其是 `ɪ`。比如，*individual*, `/ˌɪn·dəˈvɪdʒ·u·əl/`，实际上会被读作 `ˌɪn·dəˈvɪdʒ·ə·wəl`<span class="speak-word-inline" data-audio-us-male="/audios/us/individual-us-male.mp3" data-audio-us-female="/audios/us/individual-us-female.mp3"></span> —— `u` 也变成了 `ə`，而后 `u` 和 `ə` 之间有个加音 `w`…… 事实上，现在已经有很多词典干脆直接标注成了后者。