The second syllable, unstressed, begins with the F consonant sound, ff, ff, so the bottom lip will come up and make contact with the bottom of the top front teeth, ff, ff, -ffee, -ffee, -ffee.
第二音节, 无重音,以 F 辅音 ff, ff 开头,所以下唇会向上与上门牙的底部接触, ff, ff, -ffee, -ffee, -ffee。