diff --git a/book/source/04-certificates.md b/book/source/04-certificates.md
index 24b4a09..7cb7f9f 100644
--- a/book/source/04-certificates.md
+++ b/book/source/04-certificates.md
@@ -251,7 +251,7 @@ Additionally, OpenPGP allows modeling User ID-specific preferences. The idea is
 
 ## A typical OpenPGP certificate, revisited
 
-Following our review of how keys and identity components are linked, let's reexamine the OpenPGP certificate from {numref}`fig-openpgp-certificate-components`. Our focus not extends to all of its binding signatures and the direct key signature that contains metadata for the full certificate:
+Following our review of how keys and identity components are linked, let's reexamine the OpenPGP certificate from {numref}`fig-openpgp-certificate-components`. Our focus now extends to all of its binding signatures and the direct key signature that contains metadata for the full certificate:
 
 ```{figure} diag/OpenPGP_Certificate.png
 :name: fig-openpgp-certificate