错误C2143:语法错误:缺少';'在名称空间之前

I am VERY new to C++ and Open GL and I have been trying to display 3D objects in a scene. it worked fine with one but when I tried to alter my code to add a second, my code regarding the HUD text showing the camera location started giving errors. The error above is shown and it is apparently in the sstream file (#include). I have tried searching around and asking for help but there is nothing that helps/that I understand. When I comment-out the #include line and the code that uses it, I get a similar saying "error C2143: syntax error : missing ';' before 'using'" in my main.cpp file.I am VERY new to C++ and Open GL and I have bee