Fix grammar in HACKING.rst
diff --git a/HACKING.rst b/HACKING.rst
index 104118c..097b695 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -1,11 +1,11 @@
Running YAPF on itself
----------------------
-The run YAPF on all of YAPF::
+To run YAPF on all of YAPF::
$ PYTHONPATH=$PWD/yapf python -m yapf -i -r .
-The run YAPF on just the files changed in in the curent git branch::
+To run YAPF on just the files changed in the curent git branch::
$ PYTHONPATH=$PWD/yapf python -m yapf -i $(git diff --name-only @{upstream})