docs minor grammar fix

README.md

 # OptiOrch
 
-A toolchain which integrates the optimization framework “MOO4Modelica” and the orchestration workflow “ModelicaOrch” to achieve optimal control in Modelica-based simulations.
+A toolchain that integrates the optimization framework “MOO4Modelica” and the orchestration workflow “ModelicaOrch” to achieve optimal control in Modelica-based simulations.
 
-**MOO4Modelica:** The optimization framework which supports both single- and multi-objective parameter optimization.
+**MOO4Modelica:** The optimization framework that supports both single- and multi-objective parameter optimization.
 **ModelicaOrch:** The orchestration workflow to dynamically adapt models based on real-time input data.
 
 GitHub Page: [https://wangzizhe.github.io/OptiOrch](https://wangzizhe.github.io/OptiOrch)
@@ -34,7 +34,7 @@ GitHub Page: [https://wangzizhe.github.io/OptiOrch](https://wangzizhe.github.io/
 
 * **Feature Model Transformation**
   * `modelica.g4`: an ANTLR4 grammar for Modelica files
-  * `parse_modelica.py`: parse a Modelica model to extract it components and their parameters
+  * `parse_modelica.py`: parse a Modelica model to extract its components and their parameters
   * `feature_model.py`: create a feature model and add the extracted components
 * **Optimization Operation**
   * `config.json` & `config.py`: global settings and configurations