diff --git a/docs/commands/builtin/let.md b/docs/commands/builtin/let.md
index 1d4f1ca..5f1c2db 100644
--- a/docs/commands/builtin/let.md
+++ b/docs/commands/builtin/let.md
@@ -41,12 +41,13 @@ command](../../syntax/ccmd/arithmetic_eval.md):
$ echo "$a - $b - $?"
4 - 2 - 0
- Remember that inside arithmetic evaluation contexts, all
-other expansions are processed as usual (from left-to-right), and the
-resulting text is evaluated as an arithmetic expression. Arithmetic
-already has a way to control precedence using parentheses, so it's very
-rare to need to nest arithmetic expansions within one another. It's
-used above only to illustrate how this precedence works.
+!!! INFO ""
+ Remember that inside arithmetic evaluation contexts, all
+ other expansions are processed as usual (from left-to-right), and the
+ resulting text is evaluated as an arithmetic expression. Arithmetic
+ already has a way to control precedence using parentheses, so it's very
+ rare to need to nest arithmetic expansions within one another. It's
+ used above only to illustrate how this precedence works.
Unlike `((`, being a simple command `let` has its own environment. In
Bash, built-ins that can set variables process any arithmetic under
diff --git a/docs/commands/builtin/read.md b/docs/commands/builtin/read.md
index fa3aa59..830c72a 100644
--- a/docs/commands/builtin/read.md
+++ b/docs/commands/builtin/read.md
@@ -20,17 +20,16 @@ If `` is given, the line is word-split using
``. The remaining words are all assigned to the last `` if
more words than variable names are present.
- If no `` is given, the whole line
-read (without performing word-splitting!) is assigned to the shell
-variable [REPLY](../../syntax/shellvars.md#REPLY). Then, `REPLY` really contains
-the line as it was read, without stripping pre- and postfix spaces and
-other things!
+!!! INFO
+ If no `` is given, the whole line
+ read (without performing word-splitting!) is assigned to the shell
+ variable [REPLY](../../syntax/shellvars.md#REPLY). Then, `REPLY` really contains
+ the line as it was read, without stripping pre- and postfix spaces and
+ other things!
- while read -r; do
- printf '"%s"\n' "$REPLY"
- done <<<" a line with prefix and postfix space "
-
-
+ while read -r; do
+ printf '"%s"\n' "$REPLY"
+ done <<<" a line with prefix and postfix space "
If a timeout is given, or if the shell variable
[TMOUT](../../syntax/shellvars.md#TMOUT) is set, it is counted from initially
diff --git a/docs/howto/mutex.md b/docs/howto/mutex.md
index a765882..211356b 100644
--- a/docs/howto/mutex.md
+++ b/docs/howto/mutex.md
@@ -61,8 +61,9 @@ they are succesfully locked, and can operate without colliding. Setting
the timestamp is similar: One step to check the timespamp, a second step
to set the timestamp.
- **Conclusion:** We need an
-operation that does the check and the locking in one step.
+!!! NOTE ""
+ **Conclusion:** We need an
+ operation that does the check and the locking in one step.
A simple way to get that is to create a **lock directory** - with the
mkdir command. It will: