diff --git a/Marlin/pins_RUMBA.h b/Marlin/pins_RUMBA.h
index dcc5bee2e0..5d221cc290 100644
--- a/Marlin/pins_RUMBA.h
+++ b/Marlin/pins_RUMBA.h
@@ -100,7 +100,7 @@
 #endif
 
 #if TEMP_SENSOR_2 == -1
-  #define TEMP_2_PIN        7   // Analog Input (connector *K3* on RUMBA thermocouple ADD ON is used <-- this can not be used when TEMP_SENSOR_BED is defined as thermocouple)
+  #define TEMP_2_PIN        7   // Analog Input (connector *K3* on RUMBA thermocouple ADD ON is used <-- this can't be used when TEMP_SENSOR_BED is defined as thermocouple)
 #else
   #define TEMP_2_PIN       13   // Analog Input (default connector for thermistor *T2* on rumba board is used)
 #endif
@@ -109,7 +109,7 @@
 //#define TEMP_X_PIN         12   // Analog Input (default connector for thermistor *T3* on rumba board is used)
 
 #if TEMP_SENSOR_BED == -1
-  #define TEMP_BED_PIN      7   // Analog Input (connector *K3* on RUMBA thermocouple ADD ON is used <-- this can not be used when TEMP_SENSOR_2 is defined as thermocouple)
+  #define TEMP_BED_PIN      7   // Analog Input (connector *K3* on RUMBA thermocouple ADD ON is used <-- this can't be used when TEMP_SENSOR_2 is defined as thermocouple)
 #else
   #define TEMP_BED_PIN     11   // Analog Input (default connector for thermistor *THB* on rumba board is used)
 #endif