--- freem/doc/freem.texi	2025/05/05 12:51:46	1.46
+++ freem/doc/freem.texi	2025/05/05 13:13:39	1.48
@@ -271,12 +271,14 @@ Refers to an M intrinsic special variabl
 Indicates a @emph{list} of the following item, e.g., @emph{L gvn} means @emph{list of global variable names}.
 @item @emph{lvn}
 Refers to the name of an M local variable.
+@item @emph{postcondition}
+A @emph{tvexpr} immediately following a command verb affecting that command's execution.
 @item @emph{strlit}
 Refers to an M string literal.
 @item @emph{ssvn}
 Refers to the name of an M structured system variable.
 @item @emph{tvexpr}
-Refers to a truth-valued expression.
+Refers to a truth-valued expression, i.e., an expression interpreted as a truth value.
 @end table
 
 @node A Note on Standards
@@ -2043,9 +2045,9 @@ Identical to @ref{$TRANSLATE()}, except
 * WRITE::                               Write output to current input/output device.
 * XECUTE::                              Interpret string as M code.
 * ZASSERT::                             Raise error when a conditional expression evaluates @emph{false}.
-* ZBREAK::                              Unknown.
+* ZBREAK::                              Enable/disable ZBREAK mode.
 * ZCONST::                              Define a constant that cannot be altered after initial definition.
-* ZGO::                                 Unknown.
+* ZGOTO::                               @code{GOTO} with @code{BREAK} control.
 * ZHALT::                               Unknown.
 * ZINSERT::                             Insert code into routine buffer.
 * ZJOB::                                Invokes a job, ignoring any timeouts.
@@ -3363,6 +3365,14 @@ DEFAULT.USER> ZASSERT:DEBUG 1=0
 @cindex commands, non-standard
 @emph{FreeM Extension}
 
+Sets or clears the @code{ZBREAK} flag@footnote{NOTE: FreeM team needs to investigate how @code{zbreakon} and @code{zbflag} affect program execution.}, based on the result of evaluating @emph{tvexpr}.
+
+@emph{Syntax}
+
+@example
+ZBREAK @emph{tvexpr}
+@end example
+
 @node ZCONST
 @section ZCONST
 @cindex ZCONST
@@ -3380,14 +3390,30 @@ Constants must only be locals, and globa
 @code{ZCONST@emph{:postcondition} @emph{mref1}=@emph{initial-value1},...,@emph{mrefN}=@emph{initial-valueN}}
 @end example
 
-@node ZGO
-@section ZGO
-@cindex ZGO
-@cindex commands, ZGO
+@node ZGOTO
+@section ZGOTO
+@cindex ZGOTO
+@cindex commands, ZGOTO
 @cindex commands, implementation-specific
 @cindex commands, non-standard
 @emph{FreeM Extension}
 
+In its argumented form, enables @code{BREAK} mode and branches unconditionally to @emph{entryref}.
+
+@emph{Syntax}
+
+@example
+ZGOTO @emph{entryref}
+@end example
+
+In its argumented form, resumes execution after a @code{BREAK}.
+
+@emph{Syntax}
+
+@example
+ZGOTO
+@end example
+
 @node ZHALT
 @section ZHALT
 @cindex ZHALT
@@ -3396,6 +3422,22 @@ Constants must only be locals, and globa
 @cindex commands, non-standard
 @emph{FreeM Extension}
 
+In its single-argumented form, @code{ZHALT} command is used to exit the FreeM process with a specific return value @emph{intexpr}.
+
+@emph{Syntax}
+
+@example
+ZHALT @emph{intexpr}
+@end example
+
+In its argumentless form, @code{ZHALT} is synonymous with @code{HALT}.
+
+@emph{Syntax}
+
+@example
+ZHALT
+@end example
+
 @node ZINSERT
 @section ZINSERT
 @cindex ZINSERT