diff --git a/_macros.qmd b/_macros.qmd
index 10effdfe..799ff619 100644
--- a/_macros.qmd
+++ b/_macros.qmd
@@ -5,6 +5,7 @@
 \newcommand{\Vgs}[1][]{V_\mathrm{gs#1}}
 \newcommand{\VDS}[1][]{V_\mathrm{DS#1}}
 \newcommand{\Vds}[1][]{V_\mathrm{ds#1}}
+\newcommand{\VSB}[1][]{V_\mathrm{sb#1}}
 \newcommand{\vgs}[1][]{v_\mathrm{gs#1}}
 \newcommand{\vds}[1][]{v_\mathrm{ds#1}}
 \newcommand{\Vth}[1][]{V_\mathrm{th#1}}
diff --git a/_sec_first_steps.qmd b/_sec_first_steps.qmd
index 5efa12e9..c5b7a3cf 100644
--- a/_sec_first_steps.qmd
+++ b/_sec_first_steps.qmd
@@ -67,7 +67,7 @@ Please try to execute the following steps and answer these questions:
    2. If you would have to size an inverter, what would be the ideal ratio of $W_p/W_n$? Will you exactly design this ratio, or are the reasons to deviate?
    3. There are LV and HV MOSFETs, and you investigated the difference in performance. What is the rationale when designing circuits for selection either an LV type, and when to choose an HV type?
 6. Build a test bench to explore the body effect, start with LV NMOS.
-   1. What happens when $V_\mathrm{BS} \neq 0$?
+   1. What happens when $\VSB \neq 0$?
 :::
 
 ### Small-Signal MOSFET Model {#sec-mosfet-smallsignal-model}