Ruby: Incompatible encoding regexp match (UTF-8 regexp with ASCII-8BIT string)

ruby出現錯誤訊息：Incompatible encoding regexp match (UTF-8 regexp with ASCII-8BIT string)

用force_encoding強迫指定編碼即可。for example,

sentence=row1[0].force_encoding('utf-8').gsub(reg,cor_array[count].force_encoding('utf-8')).strip