With the rapid growth of digitization and multimedia, multimodal argumentation in advertisements has become a key focus in pragmatics and argumentation theory. Print advertisements, with their concise and elliptical communication, often rely on images to build logical coherence and practical effectiveness, presenting a unique challenge for multimodal argumentation research. In response, this paper combines a pragmatic perspective with argumentation theory to analyze the visual and linguistic elements as well as argumentation schemes in advertisements. It proposes a method for analyzing and evaluating multimodal arguments, particularly double-mode arguments in advertisements. This method consists of three steps: (1) the pragmatic interpretation of visual and verbal information in advertisements, (2) the reconstruction of argumentation structures including the typical argumentation schemes and their connections in print advertisements, and (3) the evaluation of reconstructed arguments based on argumentation scheme theory. By applying this method to the case study of the well-known commercial advertisement for the Sauce-flavored Latte, it offers an analytical framework for the systematic analysis and evaluation of double-mode argumentation in advertisements, thereby providing theoretical support and practical guidance for optimizing advertising design, fostering critical thinking in consumers, and identifying false advertisements.