Fix two grammatical errors

Signed-off-by: Thomas Ackermann <[email protected]>

Author: tacker66

book/09-git-and-other-scms/sections/client-tfs.asc

@@ -134,7 +134,7 @@ Git-tfs maps the branch you cloned from to `tfs/default`, and others get their o
 
 Another thing to notice is the `git-tfs-id:` lines in the commit messages.
 Instead of tags, git-tfs uses these markers to relate TFVC changesets to Git commits.
-This has the implication that your Git commits will have a different SHA-1 hash before and after they has been pushed to TFVC.
+This has the implication that your Git commits will have a different SHA-1 hash before and after they have been pushed to TFVC.
 
 ===== Git-tf[s] Workflow
 
@@ -259,7 +259,7 @@ There's a new `TFS_C35348` tag, indicating that TFVC is storing the exact same s
 It's important to note that not every Git commit needs to have an exact counterpart in TFVC; the `6eb3eb5` commit, for example, doesn't exist anywhere on the server.
 
 That's the main workflow.
-There are a couple other considerations you'll want to keep in mind:
+There are a couple of other considerations you'll want to keep in mind:
 
 * There is no branching.
   Git-tf can only create Git repositories from one TFVC branch at a time.