Typo fix (#12230)

Typo fix


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man/mono.1

@@ -28,7 +28,7 @@ to it.  The
 .I file
 is an ECMA assembly.  They typically have a .exe or .dll extension.
 .PP
-These executables can reference additionaly functionality in the form
+These executables can reference additional functionality in the form
 of assembly references.  By default those assembly references are
 resolved as follows: the \fBmscorlib.dll\fR is resolved from the
 system profile that is configured by Mono, and other assemblies are
@@ -37,8 +37,8 @@ loaded from the Global Assembly Cache (GAC).
 The runtime contains a native code generator that transforms the
 Common Intermediate Language into native code.
 .PP
-The code generator can operate in two modes: just in time compilation
-(JIT) or ahead of time compilation (AOT).  Since code can be
+The code generator can operate in two modes: Just-in-time compilation
+(JIT) or Ahead-of-time compilation (AOT).  Since code can be
 dynamically loaded, the runtime environment and the JIT are always
 present, even if code is compiled ahead of time.
 .PP