Evaluating two 7th grade texts of "pyramid of energy flow"

This study investigates the differences between two texts (X-version and Y-version) regarding pyramid of energy flow in 7th grade science textbooks, conducting a stepwise regression analysis of language base on systemic functional linguistics. The analysis required studying the number of events, lexical density, zero anaphora, nominal groups, technical construction, and cohesion, to clarify the differences between the two texts. The results of this study showed no differences between these two texts regarding the number of events and lexical density. The Y-version provided more cues for readers to retrace the zero anaphora and understand the taxonomy of nominal groups. For providing interpretations of scientific concepts, the Y-version was more cohesive compared to the X-version by using more language resources, such as conjunctions and adverbs. Therefore, evaluations of the texts should consider the features of Mandarin and the language of science.