diff --git a/strans.c b/strans.c
index a137409..c1c1e39 100644
--- a/strans.c
+++ b/strans.c
@@ -159,6 +159,8 @@ dictqmap(Im *im)
 
 	clearkouho();
 	show();
+	if(im->l->map == nil)
+		return;
 	if(!mapget(im->l->map, &im->pre, &dict))
 		return;
 	dictsend(im, &dict);
@@ -374,6 +376,16 @@ ctrlkey(Rune c)
 	return c;
 }
 
+static Rune
+kokey(Rune c, u32int mod)
+{
+	if(c >= 'A' && c <= 'Z')
+		c += 'a' - 'A';
+	if((mod & Mshift) && c >= 'a' && c <= 'z')
+		c -= 'a' - 'A';
+	return c;
+}
+
 static int
 ismodkey(u32int ks)
 {
@@ -694,6 +706,8 @@ keystroke(u32int ks, u32int mod, Str *com)
 		reset();
 		return 1;
 	}
+	if(im.l->lang == LangKO)
+		ks = kokey(ks, mod);
 	n = dotrans(ks, com);
 	show();
 	return n;
diff --git a/tests/engine_test.c b/tests/engine_test.c
index e75306b..390184e 100644
--- a/tests/engine_test.c
+++ b/tests/engine_test.c
@@ -189,6 +189,63 @@ engine_telex_history_bound(struct ct *t)
 	CT_EQ_INT(t, 0, im.raw.n);
 }
 
+void
+engine_korean_modifiers_and_backspace(struct ct *t)
+{
+	static const struct {
+		Rune key;
+		char *plain;
+		char *shifted;
+	} cases[] = {
+		{ 'r', "ㄱ", "ㄲ" }, { 'e', "ㄷ", "ㄸ" },
+		{ 'q', "ㅂ", "ㅃ" }, { 't', "ㅅ", "ㅆ" },
+		{ 'w', "ㅈ", "ㅉ" }, { 'o', "ㅐ", "ㅒ" },
+		{ 'p', "ㅔ", "ㅖ" },
+	};
+	Str com;
+	int i;
+
+	for(i = 0; i < nelem(cases); i++){
+		init();
+		im.l = getlang(LangKO);
+		sclear(&com);
+		CT_CHECK(t, keystroke(cases[i].key, 0, &com));
+		checkstr(t, "plain Korean key", cases[i].plain, &im.pre);
+
+		init();
+		im.l = getlang(LangKO);
+		sclear(&com);
+		CT_CHECK(t, keystroke(cases[i].key, Mshift, &com));
+		checkstr(t, "shifted Korean key", cases[i].shifted, &im.pre);
+
+		init();
+		im.l = getlang(LangKO);
+		sclear(&com);
+		CT_CHECK(t, keystroke(cases[i].key - 'a' + 'A', 0, &com));
+		checkstr(t, "Caps Lock Korean key", cases[i].plain, &im.pre);
+
+		init();
+		im.l = getlang(LangKO);
+		sclear(&com);
+		CT_CHECK(t, keystroke(cases[i].key, Mshift, &com));
+		checkstr(t, "Shift+Caps Korean key", cases[i].shifted, &im.pre);
+	}
+
+	init();
+	im.l = getlang(LangKO);
+	sclear(&com);
+	if(typekeys(t, "rkr", &com)){
+		checkstr(t, "Korean engine preedit", "각", &im.pre);
+		CT_CHECK(t, keystroke(Kback, 0, &com));
+		checkstr(t, "Korean final backspace", "가", &im.pre);
+		CT_CHECK(t, keystroke(Kback, 0, &com));
+		checkstr(t, "Korean vowel backspace", "ㄱ", &im.pre);
+		CT_CHECK(t, keystroke(Kback, 0, &com));
+		CT_EQ_INT(t, 0, im.pre.n);
+		CT_CHECK(t, !keystroke(Kback, 0, &com));
+	}
+}
+
 void
 engine_language_switch_state(struct ct *t)
 {
diff --git a/tests/ko_test.c b/tests/ko_test.c
index 405d60a..0c42c57 100644
--- a/tests/ko_test.c
+++ b/tests/ko_test.c
@@ -1,5 +1,27 @@
 #include "test.h"
 
+static Str
+kotrans(char *keys)
+{
+	Emit e;
+	Im state;
+	Str out;
+	char *p;
+
+	memset(&state, 0, sizeof state);
+	state.l = getlang(LangKO);
+	sclear(&out);
+	for(p = keys; *p != '\0'; p++){
+		e = transko(&state, (uchar)*p);
+		sappend(&out, &e.s);
+		state.pre = e.next;
+		if(!e.eat)
+			sputr(&out, (uchar)*p);
+	}
+	sappend(&out, &state.pre);
+	return out;
+}
+
 void
 korean_sequences(struct ct *t)
 {
@@ -14,39 +36,70 @@ korean_sequences(struct ct *t)
 		{ "Rk", "까" },
 		{ "rk1", "가1" },
 	};
-	Emit e;
-	Im state;
 	Str out;
-	Rune key;
-	char *p;
 	int i;
 
 	for(i = 0; i < nelem(cases); i++){
-		memset(&state, 0, sizeof state);
-		state.l = getlang(LangKO);
-		sclear(&out);
-		for(p = cases[i].keys; *p != '\0'; p++){
-			key = (uchar)*p;
-			e = transko(&state, key);
-			sappend(&out, &e.s);
-			state.pre = e.next;
-			if(!e.eat)
-				sputr(&out, key);
-		}
-		sappend(&out, &state.pre);
+		out = kotrans(cases[i].keys);
 		checkstr(t, cases[i].keys, cases[i].want, &out);
 	}
 }
 
+void
+korean_compound_vowels(struct ct *t)
+{
+	static const struct { char *keys, *want; } cases[] = {
+		{ "hk", "ㅘ" }, { "ho", "ㅙ" }, { "hl", "ㅚ" },
+		{ "nj", "ㅝ" }, { "np", "ㅞ" }, { "nl", "ㅟ" },
+		{ "ml", "ㅢ" },
+	};
+	Str out;
+	int i;
+
+	for(i = 0; i < nelem(cases); i++){
+		out = kotrans(cases[i].keys);
+		checkstr(t, cases[i].keys, cases[i].want, &out);
+	}
+}
+
+void
+korean_compound_finals(struct ct *t)
+{
+	static const struct { char *keys, *want, *split; } cases[] = {
+		{ "rkrt", "갃", "각사" }, { "rksw", "갅", "간자" },
+		{ "rksg", "갆", "간하" }, { "rkfr", "갉", "갈가" },
+		{ "rkfa", "갊", "갈마" }, { "rkfq", "갋", "갈바" },
+		{ "rkft", "갌", "갈사" }, { "rkfx", "갍", "갈타" },
+		{ "rkfv", "갎", "갈파" }, { "rkfg", "갏", "갈하" },
+		{ "rkqt", "값", "갑사" },
+	};
+	char keys[16];
+	Str out;
+	int i;
+
+	for(i = 0; i < nelem(cases); i++){
+		out = kotrans(cases[i].keys);
+		checkstr(t, cases[i].keys, cases[i].want, &out);
+		snprint(keys, sizeof keys, "%sk", cases[i].keys);
+		out = kotrans(keys);
+		checkstr(t, keys, cases[i].split, &out);
+	}
+}
+
 void
 korean_backspace(struct ct *t)
 {
 	static const struct { char *before, *after; } cases[] = {
 		{ "ㄱ", "" },
 		{ "가", "ㄱ" },
-		{ "과", "고" },
+		{ "과", "고" }, { "괘", "고" }, { "괴", "고" },
+		{ "궈", "구" }, { "궤", "구" }, { "귀", "구" },
+		{ "긔", "그" },
 		{ "각", "가" },
-		{ "갃", "각" },
+		{ "갃", "각" }, { "갅", "간" }, { "갆", "간" },
+		{ "갉", "갈" }, { "갊", "갈" }, { "갋", "갈" },
+		{ "갌", "갈" }, { "갍", "갈" }, { "갎", "갈" },
+		{ "갏", "갈" }, { "값", "갑" },
 	};
 	Im state;
 	int i;
diff --git a/tests/test.h b/tests/test.h
index 00832f5..7641cac 100644
--- a/tests/test.h
+++ b/tests/test.h
@@ -23,6 +23,8 @@ void	trie_exact_prefix_and_duplicate(struct ct*);
 void	production_maps_load(struct ct*);
 void	transmap_states(struct ct*);
 void	korean_sequences(struct ct*);
+void	korean_compound_vowels(struct ct*);
+void	korean_compound_finals(struct ct*);
 void	korean_backspace(struct ct*);
 void	vietnamese_transitions(struct ct*);
 void	vietnamese_backspace(struct ct*);
@@ -33,6 +35,7 @@ void	engine_selects_visible_candidate(struct ct*);
 void	engine_commit_contract(struct ct*);
 void	engine_language_switch_state(struct ct*);
 void	engine_telex_history_bound(struct ct*);
+void	engine_korean_modifiers_and_backspace(struct ct*);
 void	engine_japanese_readings(struct ct*);
 void	engine_japanese_candidates(struct ct*);
 void	engine_japanese_backspace_and_boundaries(struct ct*);
diff --git a/tests/unit_test.c b/tests/unit_test.c
index 97662db..667e509 100644
--- a/tests/unit_test.c
+++ b/tests/unit_test.c
@@ -72,6 +72,8 @@ static const struct ct_test tests[] = {
 	{ "map/production-lifecycle", production_maps_load },
 	{ "transmap/states", transmap_states },
 	{ "hangul/sequences", korean_sequences },
+	{ "hangul/compound-vowels", korean_compound_vowels },
+	{ "hangul/compound-finals", korean_compound_finals },
 	{ "hangul/backspace", korean_backspace },
 	{ "telex/transitions", vietnamese_transitions },
 	{ "telex/backspace", vietnamese_backspace },
@@ -82,6 +84,7 @@ static const struct ct_test tests[] = {
 	{ "engine/commit-contract", engine_commit_contract },
 	{ "engine/language-switch-state", engine_language_switch_state },
 	{ "engine/telex-history-bound", engine_telex_history_bound },
+	{ "engine/korean-modifiers-backspace", engine_korean_modifiers_and_backspace },
 	{ "engine/japanese-readings", engine_japanese_readings },
 	{ "engine/japanese-candidates", engine_japanese_candidates },
 	{ "engine/japanese-backspace-boundaries", engine_japanese_backspace_and_boundaries },