
Some people speak with a stutter (口吃). Sometimes they can’t say some words ___1___ (clear). Sometimes they say the same word many ___2___ (time). Sometimes they stop for a short time when they speak.
More than 70 million people stutter around ___3___ world. 5% of the children stutter at some time in ___4___ (they) lives. Some people stutter all their life.
Scientists say that ___5___ (that) people have different brains. Also, more people in the same family stutter. It is common. Men stutter ___6___ (much) often than women.