Before revision:  However, in real-world environments, a human usually only has a general goal (e.g., general direction or area in motion planning) at the beginning of the cooperation  which needs to be clarified to a specific goal (e.g., an exact position) during cooperation.
After revision:  However, in real-world environments, a human usually only has a general goal (e.g., general direction or area in motion planning) at the beginning of the cooperation , which needs to be clarified to a specific goal (e.g., an exact position) during cooperation.