Edits to devleoper doc files 2

src/input.cpp

@@ -78,7 +78,7 @@ template <typename T> static Command *command_creator(LAMMPS *lmp)
 
 The Input class contains methods for reading, pre-processing and
 parsing LAMMPS commands and input files and will dispatch commands
-to the respective class instances or contains the code to execute
+to the respective class instances or contain the code to execute
 the commands directly.  It also contains the instance of the
 Variable class which performs computations and text substitutions.
 
@@ -320,8 +320,8 @@ void Input::file()
  *
 \verbatim embed:rst
 
-This function opens the file at the path *filename*, put the current
-file pointer stored in *infile* on a stack and instead assign *infile*
+This function opens the file at the path *filename*, puts the current
+file pointer stored in *infile* on a stack and instead assigns *infile*
 with the newly opened file pointer.  Then it will call the
 :cpp:func:`Input::file() <LAMMPS_NS::Input::file()>` function to read,
 parse and execute the contents of that file.  When the end of the file