To chew thoroughly and eating slowly are necessary for good dige

To chew thoroughly and eating slowly are necessary for good digestion.
【正确答案】：To chew thoroughly and eat slowly are necessary for good digestion.
【题目解析】：本句的错误在于句子的主语应该以相同语法形式的短语的形式平行出现，但没有做到。所以，我们采用将不定式短语改写方式来改写本题。