Third tone may change to second tone under certain situation during Chinese reading. Rule of Chinese Four Tones.

1. Four Tones Change
– ˊ ˇ ˋ
By Frances Fu 2006

2.  :
 “ ” ,
,
“ ” .
 ˊ
 ˊ
By Frances Fu 2006

3. 
 一 一,
, ˋ
 ˋ天, ˋ , ˋ
By Frances Fu 2006

4. 
 一 一,
 ˊ
 ˊ ˋ,
 ˊ ˋ,
By Frances Fu 2006

5. 
 ˋ,
, ˊ
 ˊ , ˊ ,
 ˊ , ˊ ,
By Frances Fu 2006