To the problems on software formal description and partial correctness verification, a unified frame based on XYZ/SE is proposed. The unified frame includes four steps. Software is abstracted based on stepwise idea. It uses XYZ/SE to finish formal description and partial correctness verification of whole software. It uses XYZ/SE to finish formal description and partial correctness verification of each component of software. It adjusts and validates previous inference. If inferred results are different from ...