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58-03.md

@@ -67,10 +67,11 @@ the ES: prefix (and, as we shall see, we can), we can rearrange the code
 to make it run faster on the Pentium. Without a prefix, the instructions
 execute as follows on the Pentium:
 
-
-    MOV  AH,[BX]    ;cycle 1 U-pipe
-                    ;cycle 1 V-pipe idle; reg contention
-    MOV  [DI],AH    ;cycle 2 U-pipe
+```nasm
+MOV  AH,[BX]    ;cycle 1 U-pipe
+                ;cycle 1 V-pipe idle; reg contention
+MOV  [DI],AH    ;cycle 2 U-pipe
+```
 
 The second **MOV**, being dependent on the value loaded into AH by the
 first **MOV**, can't execute until the first **MOV** is finished, so the
@@ -82,8 +83,9 @@ Advancing the destination pointer is easy to speed up: Just build the
 offset from one scanline to the next into each pixel-drawing instruction
 as a constant, as in
 
-
-    MOV [EDI+SCANOFFSET],AH
+```nasm
+MOV [EDI+SCANOFFSET],AH
+```
 
 and advance EDI only once per unrolled loop iteration.