Hellow: I am a fd fans, Now I prepare to install Mopac7 which is a fortran language software, when I make it ,I got a error message: $ make f77 -O -c -static -c -o aababc.o aababc.f make: f77: Command not found make: *** [aababc.o] Error 127 what happen with it, Could somebody tell me how to do ?Thank you very much!