Compare the power of ane-mail to convince with, for example, th persuasive power of someone talking to you face to face, with their eyes and gestures telling you that something must be done.

把一封电子邮件对你的说服力和这些的说服力相比——比如，某个人和你面对面交谈，以眼神和手势劝说你去做某件事。