请问在英文中,冒号的作用相当于分号隔开两个句子；还是相当于逗号,连接同一个句子啊?

冒号的作用1.引述别人的原话 2.解释说明如：I turned to look at the children,but there weren't any in sight:they had all run away.冒号后面的话解释其前面的话,分号是隔开两个并列句,逗号连接得既可以是并列句...