Update garbage-collection.xml readability

1. remove a typo space
2. Simplify negative style by using affirmative style

(cherry picked from commit 10bfc5c0d09d5508e3dab4c32f3368caeb5f7f56)

1 files changed, 6 insertions, 5 deletions

diff --git a/doc/manual/packages/garbage-collection.xml b/doc/manual/packages/garbage-collection.xml
index a1b0ef22a11e..b506f22b0302 100644
--- a/doc/manual/packages/garbage-collection.xml
+++ b/doc/manual/packages/garbage-collection.xml
@@ -52,12 +52,13 @@ garbage collector as follows:
 <screen>
 $ nix-store --gc</screen>
 
-The behaviour of the gargage collector is affected by the <literal>keep-
-derivations</literal> (default: true) and <literal>keep-outputs</literal>
+The behaviour of the gargage collector is affected by the 
+<literal>keep-derivations</literal> (default: true) and <literal>keep-outputs</literal>
 (default: false) options in the Nix configuration file. The defaults will ensure
-that all derivations that are not build-time dependencies of garbage collector roots
-will be collected but that all output paths that are not runtime dependencies
-will be collected. (This is usually what you want, but while you are developing
+that all derivations that are build-time dependencies of garbage collector roots
+will be kept and that all output paths that are runtime dependencies
+will be kept as well. All other derivations or paths will be collected. 
+(This is usually what you want, but while you are developing
 it may make sense to keep outputs to ensure that rebuild times are quick.)
 
 If you are feeling uncertain, you can also first view what files would