+4 = 7

ㄅㄧˇ

ㄅㄧˇbǐ
+4 = 7

ㄅㄧˋ

ㄅㄧˋbì
+4 = 7

ㄆㄧˇ

ㄆㄧˇpǐ
used as phonetic bi- or pi-
(phonetisch bi- oder pi-)​