speak是说话的意思，而 pronounce则是读音或者发音的意思，区别可以从以下例子看出：
You are a teacher, when you speak to your students, you have to speak clearly and pronounce accurately. 你是老师，当你和你的学生说话时，你必须说得清楚，发音准确。
水利万物而不争,
而万物莫能与之争。
