diff --git a/README.md b/README.md
index b80d71b..e70931c 100644
--- a/README.md
+++ b/README.md
@@ -18,15 +18,15 @@ Usage
     make
     echo "0 1\n0 2\n1 0\n1 3\n2 0\n3 0\n3 1\n3 2" | ./circuits_hawick 4
 
-First argument is the number of vertices. Subsequent arguments are ordered
-pairs of comma separated vertices that make up the directed edges of the
+First argument is the number of vertices. Ordered pairs of space separated
+vertices are given via standard input and make up the directed edges of the
 graph.
 
 DOT file input
 --------------
 
 For simplicity, there is no DOT file parser included but the following allows
-to create a suitable argument string for simple DOT graphs.
+to create a suitable argument string and standard input for simple DOT graphs.
 
 Given a DOT file of a simple (no labels, colors, styles, only pairs of
 vertices...) directed graph, the following lines generate the number of
@@ -35,7 +35,7 @@ vertices as well as the edge list expected on standard input.
         sed -n -e '/^\s*[0-9]\+;$/p' graph.dot | wc -l
         sed -n -e 's/^\s*\([0-9]\) -> \([0-9]\);$/\1 \2/p' graph.dot
 
-The above line works on DOT files like the following:
+The above lines work on DOT files like the following:
 
     digraph G {
       0;