diff --git a/book/source/05-private.md b/book/source/05-private.md
index 56257b7..49ac43c 100644
--- a/book/source/05-private.md
+++ b/book/source/05-private.md
@@ -50,7 +50,7 @@ The TSK format can be useful for backups of OpenPGP key material, or to move a k
 See the chapter {ref}`zoom_private` for insights into the packet structure of a TSK.
 
 (encrypted_secrets)=
-## Protecting secret key material with a passphrase (using S2K)
+## Protecting private key material with a passphrase (using S2K)
 
 In OpenPGP format, private key material can be optionally protected with a [passphrase](https://en.wikipedia.org/wiki/Passphrase). This mechanism applies symmetric encryption to the private key data in component keys.
 
@@ -62,7 +62,7 @@ OpenPGP defines a mechanism called [string-to-key (S2K)](https://www.ietf.org/ar
 
 ```{figure} diag/passphrase_using_S2K.png
 
-Transforming a passphrase to a symmetric key
+Transforming a passphrase into a symmetric key
 ```
 
 The private key material for individual component keys of one certificate can be encrypted with different mechanisms, and/or using different passphrases.