This work delves into the effect of E-C ST (sight translation) on orality of texts. It nails down parameters for measuring orality, draws conclusions with the aid of both qualitative and quantitative methods, and explores underlying reasons, on the basis of which, this study also sheds light on ST teaching and textbook compilation. The current study finds that E-C ST diminishes the orality of markedly oral texts and the literateness of markedly literate ones. Markedly oral texts moving towards the literate end of the continuum after E-C ST may be explained with the Theory of Adaptation, while markedly literate texts moving towards the oral end of the continuum after E-C ST may be attributed to the fact that the total requirements may exceed the total processing capacity.