diff --git a/runtime/tutor/Make_mvc.mak b/runtime/tutor/Make_mvc.mak
index bd62016..1c5c315 100644
--- a/runtime/tutor/Make_mvc.mak
+++ b/runtime/tutor/Make_mvc.mak
@@ -27,6 +27,9 @@
 
 RM = del /q
 CP = copy /y
+PS = PowerShell.exe
+
+PSFLAGS = -NoLogo -NoProfile -Command
 
 all : $(CONVERTED)
 
@@ -34,8 +37,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -44,8 +46,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-1 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28591))
@@ -55,8 +56,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -65,8 +65,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -75,8 +74,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-7 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28597))
@@ -86,8 +84,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t CP737 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(737))
@@ -97,8 +94,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-3 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28593))
@@ -108,8 +104,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-1 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28591))
@@ -119,8 +114,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -129,8 +123,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-2 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28592))
@@ -140,8 +133,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t CP1250 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(1250))
@@ -151,8 +143,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-2 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28592))
@@ -162,8 +153,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t CP1250 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(1250))
@@ -173,8 +163,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -183,8 +172,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t CP932 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(932))
@@ -194,8 +182,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t EUC-JP $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(51932))
@@ -205,8 +192,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t EUC-KR $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(51949))
@@ -216,8 +202,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-1 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28591))
@@ -227,8 +212,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -244,8 +228,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t KOI8-R $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(20866))
@@ -255,8 +238,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t CP1251 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(1251))
@@ -266,8 +248,7 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f ISO-8859-1 -t UTF-8 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(28591)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 !ENDIF
@@ -276,20 +257,18 @@
 !IF DEFINED (ICONV)
 	$(ICONV) -f UTF-8 -t ISO-8859-9 $? >$@
 !ELSE
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::WriteAllText(\"$@\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::WriteAllText(\"$@\", \
 		[System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(65001)), \
 		[System.Text.Encoding]::GetEncoding(28599))
 !ENDIF
 
 tutor.zh.utf-8 : tutor.zh.big5
-	powershell -nologo -noprofile -Command \
-		[System.IO.File]::ReadAllText(\"$?\", \
+	$(PS) $(PSFLAGS) [System.IO.File]::ReadAllText(\"$?\", \
 		[System.Text.Encoding]::GetEncoding(950)) ^| \
 		1>nul New-Item -Force -ItemType file -Path . -Name $@
 
-clean : $(CONVERTED)
-	!$(RM) $**
+clean :
+	@for %%G in ($(CONVERTED)) do (if exist .\%%G ($(RM) %%G))
 
 # vim: set noet sw=8 ts=8 sts=0 wm=0 tw=0 ft=make:
diff --git a/runtime/tutor/Makefile b/runtime/tutor/Makefile
index 484769e..3c0fe0a 100644
--- a/runtime/tutor/Makefile
+++ b/runtime/tutor/Makefile
@@ -8,83 +8,88 @@
 # Common components
 include Make_all.mak
 
+.PHONY: all clean
+
 all: $(CONVERTED)
 
 tutor.utf-8: tutor
-	iconv -f ISO-8859-1 -t UTF-8 tutor > tutor.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.bar: tutor.bar.utf-8
-	iconv -f UTF-8 -t ISO-8859-1 tutor.bar.utf-8 > tutor.bar
+	iconv -f UTF-8 -t ISO-8859-1 $< >$@
 
 tutor.ca.utf-8: tutor.ca
-	iconv -f ISO-8859-1 -t UTF-8 tutor.ca > tutor.ca.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.eo: tutor.eo.utf-8
-	iconv -f UTF-8 -t ISO-8859-3 tutor.eo.utf-8 > tutor.eo
+	iconv -f UTF-8 -t ISO-8859-3 $< >$@
 
 tutor.de.utf-8: tutor.de
-	iconv -f ISO-8859-1 -t UTF-8 tutor.de > tutor.de.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.el: tutor.el.utf-8
-	iconv -f UTF-8 -t ISO-8859-7 tutor.el.utf-8 > tutor.el
+	iconv -f UTF-8 -t ISO-8859-7 $< >$@
 
 tutor.el.cp737: tutor.el.utf-8
-	iconv -f UTF-8 -t CP737 tutor.el.utf-8 > tutor.el.cp737
+	iconv -f UTF-8 -t CP737 $< >$@
 
 tutor.es: tutor.es.utf-8
-	iconv -f UTF-8 -t ISO-8859-1 tutor.es.utf-8 > tutor.es
+	iconv -f UTF-8 -t ISO-8859-1 $< >$@
 
 tutor.fr.utf-8: tutor.fr
-	iconv -f ISO-8859-1 -t UTF-8 tutor.fr > tutor.fr.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.hu: tutor.hu.utf-8
-	iconv -f UTF-8 -t ISO-8859-2 tutor.hu.utf-8 > tutor.hu
+	iconv -f UTF-8 -t ISO-8859-2 $< >$@
 
 tutor.hu.cp1250: tutor.hu.utf-8
-	iconv -f UTF-8 -t CP1250 tutor.hu.utf-8 > tutor.hu.cp1250
+	iconv -f UTF-8 -t CP1250 $< >$@
 
 tutor.it.utf-8: tutor.it
-	iconv -f ISO-8859-1 -t UTF-8 tutor.it > tutor.it.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.hr: tutor.hr.utf-8
-	iconv -f UTF-8 -t ISO-8859-2 tutor.hr.utf-8 > tutor.hr
+	iconv -f UTF-8 -t ISO-8859-2 $< >$@
 
 tutor.hr.cp1250: tutor.hr.utf-8
-	iconv -f UTF-8 -t CP1250 tutor.hr.utf-8 > tutor.hr.cp1250
+	iconv -f UTF-8 -t CP1250 $< >$@
 
 tutor.ja.sjis: tutor.ja.utf-8
-	iconv -f UTF-8 -t CP932 tutor.ja.utf-8 > tutor.ja.sjis
+	iconv -f UTF-8 -t CP932 $< >$@
 
 tutor.ja.euc: tutor.ja.utf-8
-	iconv -f UTF-8 -t EUC-JP tutor.ja.utf-8 > tutor.ja.euc
+	iconv -f UTF-8 -t EUC-JP $< >$@
 
 tutor.ko.euc: tutor.ko.utf-8
-	iconv -f UTF-8 -t EUC-KR tutor.ko.utf-8 > tutor.ko.euc
+	iconv -f UTF-8 -t EUC-KR $< >$@
 
 tutor.nl: tutor.nl.utf-8
-	iconv -f UTF-8 -t ISO-8859-1 tutor.nl.utf-8 > tutor.nl
+	iconv -f UTF-8 -t ISO-8859-1 $< >$@
 
 tutor.no.utf-8: tutor.no
-	iconv -f ISO-8859-1 -t UTF-8 tutor.no > tutor.no.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 # nb is an alias for no
 tutor.nb: tutor.no
-	cp tutor.no tutor.nb
+	cp $< $@
 
 tutor.nb.utf-8: tutor.no.utf-8
-	cp tutor.no.utf-8 tutor.nb.utf-8
+	cp $< $@
 
 tutor.ru: tutor.ru.utf-8
-	iconv -f UTF-8 -t KOI8-R tutor.ru.utf-8 > tutor.ru
+	iconv -f UTF-8 -t KOI8-R $< >$@
 
 tutor.ru.cp1251: tutor.ru.utf-8
-	iconv -f UTF-8 -t CP1251 tutor.ru.utf-8 > tutor.ru.cp1251
+	iconv -f UTF-8 -t CP1251 $< >$@
 
 tutor.tr.iso9: tutor.tr.utf-8
-	iconv -f UTF-8 -t ISO-8859-9 tutor.tr.utf-8 > tutor.tr.iso9
+	iconv -f UTF-8 -t ISO-8859-9 $< >$@
 
 tutor.sv.utf-8: tutor.sv
-	iconv -f ISO-8859-1 -t UTF-8 tutor.sv > tutor.sv.utf-8
+	iconv -f ISO-8859-1 -t UTF-8 $< >$@
 
 tutor.zh.utf-8: tutor.zh.big5
-	iconv -f BIG-5 -t UTF-8 tutor.zh.big5 > tutor.zh.utf-8
+	iconv -f BIG-5 -t UTF-8 $< >$@
+
+clean:
+	for G in $(CONVERTED); do if [ -f $$G ]; then rm -f $$G; fi; done