diff --git a/runtime/syntax/pamconf.vim b/runtime/syntax/pamconf.vim
index 10d667b..2913284 100644
--- a/runtime/syntax/pamconf.vim
+++ b/runtime/syntax/pamconf.vim
@@ -1,7 +1,8 @@
 " Vim syntax file
 " Language:             pam(8) configuration file
 " Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2011-08-03
+" Latest Revision:      2020/08/04
+" Changes By:		Haochen Tong
 
 
 if exists("b:current_syntax")
@@ -11,23 +12,32 @@
 let s:cpo_save = &cpo
 set cpo&vim
 
-syn match   pamconfService          '^[[:graph:]]\+'
-                                    \ nextgroup=pamconfType,
-                                    \ pamconfServiceLineCont skipwhite
+let s:has_service_field = exists("b:pamconf_has_service_field")
+      \ ? b:pamconf_has_service_field
+      \ : expand('%:t') == 'pam.conf' ? 1 : 0
+
+syn match   pamconfType             '-\?[[:alpha:]]\+'
+                                    \ contains=pamconfTypeKeyword
+                                    \ nextgroup=pamconfControl,
+                                    \ pamconfTypeLineCont skipwhite
+
+syn keyword pamconfTypeKeyword      contained account auth password session
+
+if s:has_service_field
+    syn match   pamconfService          '^[[:graph:]]\+'
+                                        \ nextgroup=pamconfType,
+                                        \ pamconfServiceLineCont skipwhite
+
+    syn match   pamconfServiceLineCont  contained '\\$'
+                                        \ nextgroup=pamconfType,
+                                        \ pamconfServiceLineCont skipwhite skipnl
+endif
 
 syn keyword pamconfTodo             contained TODO FIXME XXX NOTE
 
 syn region  pamconfComment          display oneline start='#' end='$'
                                     \ contains=pamconfTodo,@Spell
 
-syn match   pamconfServiceLineCont  contained '\\$'
-                                    \ nextgroup=pamconfType,
-                                    \ pamconfServiceLineCont skipwhite skipnl
-
-syn keyword pamconfType             account auth password session
-                                    \ nextgroup=pamconfControl,
-                                    \ pamconfTypeLineCont skipwhite
-
 syn match   pamconfTypeLineCont     contained '\\$'
                                     \ nextgroup=pamconfControl,
                                     \ pamconfTypeLineCont skipwhite skipnl
@@ -98,7 +108,8 @@
 hi def link pamconfComment          Comment
 hi def link pamconfService          Statement
 hi def link pamconfServiceLineCont  Special
-hi def link pamconfType             Type
+hi def link pamconfType             Special
+hi def link pamconfTypeKeyword      Type
 hi def link pamconfTypeLineCont     pamconfServiceLineCont
 hi def link pamconfControl          Macro
 hi def link pamconfControlBegin     Delimiter