-\fBif\-elseif\-else\-endif\fP block where only one of the \fIformat
-text\fP segments is interpreted.
-
-The `%<' and `%?' control escapes causes a condition to be evaluated.
-This condition
-may be either a \fIcomponent\fP or a \fIfunction\fP.
-The four constructs have the following syntax:
-.sp 1
-.nf
- %<{component}
- %<(function)
- %?{component}
- %?(function)
-.fi
-.sp
-These control escapes test whether the function or component value is
-non-zero (for integer-valued escapes), or non-empty (for string-valued
-escapes).
-
-If this test evaulates true, then the format text up to the next
-corresponding control escape (one of `%|', `%?', or `%>') is interpreted
-normally. Next, all format text (if any) up to the corresponding `%>'
-control escape is skipped. The `%>' control escape is not interpreted;
-normal interpretation resumes after the `%>' escape.
-
-If the test evaluates false, however, then the format text up to
-the next corresponding control escape (again, one of `%|', `%?', or
-`%>') is skipped, instead of being interpreted. If the control escape
-encountered was `%?', then the condition associated with that control
-escape is evaluated, and interpretation proceeds after that test as
-described in the previous paragraph. If the control escape encountered
-was `%|', then the format text up to the corresponding `%>' escape is
-interpreted normally. As above, the `%>' escape is not interpreted and
-normal interpretation resumes after the `%>' escape.
-
-The `%?' control escape and its following format text is optional, and may
-be included zero or more times. The `%|' control escape and its following
-format text is also optional, and may be included zero or one times.
-
-.Uh "Function escapes"
-.ne 10
-Most functions expect an argument of a particular type:
-.sp 1
+.B if\-elseif\-else\-endif
+block where only one of the
+format-texts
+is interpreted. In other
+words, `%<' is like the "if", `%?' is like the "elseif", `%|' is like
+"else", and `%>' is like "endif".
+.PP
+A `%<' or `%?' control escape causes its condition to be evaluated.
+This condition is a
+.I component
+or
+.IR function .
+For integer valued functions or components, the condition is true
+if the function return or component value is non-zero, and false if zero.
+For string valued functions or components, the condition is true
+if the function return or component value is
+a non-empty string, and false for an empty string.
+
+.PP
+The `%?' control escape is optional, and may there may be more
+than one `%?' control escape in a conditional block.
+The `%|' control escape
+is also optional, but may be included at most once.
+
+.SS "Function escapes"
+Functions expecting an argument generally
+require an argument of a particular type.
+In addition to the number and string types,
+these include:
+.PP
+.RS 5