diff --git a/23_day/Makefile b/23_day/Makefile
index 1cad093..b46962b 100644
--- a/23_day/Makefile
+++ b/23_day/Makefile
@@ -134,9 +134,17 @@ stars2.bim : stars2.obj a_nask.obj Makefile
 stars2.hrb : stars2.bim Makefile
 	$(BIM2HRB) stars2.bim stars2.hrb 47k
 
+lines.bim : lines.obj a_nask.obj Makefile
+	$(OBJ2BIM) @$(RULEFILE) out:lines.bim stack:1k map:lines.map \
+		lines.obj a_nask.obj
+
+lines.hrb : lines.bim Makefile
+	$(BIM2HRB) lines.bim lines.hrb 48k
+
 haribote.img : ipl10.bin haribote.sys Makefile \
 		hello.hrb hello2.hrb a.hrb hello3.hrb hello4.hrb hello5.hrb \
-		winhelo.hrb winhelo2.hrb winhelo3.hrb star1.hrb stars.hrb stars2.hrb
+		winhelo.hrb winhelo2.hrb winhelo3.hrb star1.hrb stars.hrb stars2.hrb \
+		lines.hrb
 	$(EDIMG)   imgin:../z_tools/fdimg0at.tek \
 		wbinimg src:ipl10.bin len:512 from:0 to:0 \
 		copy from:haribote.sys to:@: \
@@ -154,8 +162,9 @@ haribote.img : ipl10.bin haribote.sys Makefile \
 		copy from:star1.hrb to:@: \
 		copy from:stars.hrb to:@: \
 		copy from:stars2.hrb to:@: \
+		copy from:lines.hrb to:@: \
 		imgout:haribote.img
-		
+
 # 其他指令
 
 %.gas : %.c bootpack.h Makefile
diff --git a/23_day/a_nask.nas b/23_day/a_nask.nas
index 1d78502..aec636e 100644
--- a/23_day/a_nask.nas
+++ b/23_day/a_nask.nas
@@ -14,6 +14,7 @@
 		GLOBAL	_api_free
 		GLOBAL	_api_point
 		GLOBAL	_api_refreshwin
+		GLOBAL	_api_linewin
 
 [SECTION .text]
 
@@ -150,3 +151,22 @@ _api_refreshwin:	; void api_refreshwin(int win, int x0, int y0, int x1, int y1);
 		POP		ESI
 		POP		EDI
 		RET
+
+_api_linewin:		; void api_linewin(int win, int x0, int y0, int x1, int y1, int col);
+		PUSH	EDI
+		PUSH	ESI
+		PUSH	EBP
+		PUSH	EBX
+		MOV		EDX,13
+		MOV		EBX,[ESP+20]	; win
+		MOV		EAX,[ESP+24]	; x0
+		MOV		ECX,[ESP+28]	; y0
+		MOV		ESI,[ESP+32]	; x1
+		MOV		EDI,[ESP+36]	; y1
+		MOV		EBP,[ESP+40]	; col
+		INT		0x40
+		POP		EBX
+		POP		EBP
+		POP		ESI
+		POP		EDI
+		RET
diff --git a/23_day/console.c b/23_day/console.c
index 86646ed..b7d65ad 100644
--- a/23_day/console.c
+++ b/23_day/console.c
@@ -367,6 +367,12 @@ int *hrb_api(int edi, int esi, int ebp, int esp, int ebx, int edx, int ecx, int
 	} else if (edx == 12) {
 		sht = (struct SHEET *) ebx;
 		sheet_refresh(sht, eax, ecx, esi, edi);
+	} else if (edx == 13) {
+		sht = (struct SHEET *) (ebx & 0xfffffffe);
+		hrb_api_linewin(sht, eax, ecx, esi, edi, ebp);
+		if ((ebx & 1) == 0) {
+			sheet_refresh(sht, eax, ecx, esi + 1, edi + 1);
+		}
 	}
 	return 0;
 }
@@ -392,3 +398,52 @@ int *inthandler0d(int *esp)
 	cons_putstr0(cons, s);
 	return &(task->tss.esp0);	/*强制结束程序*/
 }
+
+void hrb_api_linewin(struct SHEET *sht, int x0, int y0, int x1, int y1, int col)
+{
+	int i, x, y, len, dx, dy;
+
+	dx = x1 - x0;
+	dy = y1 - y0;
+	x = x0 << 10;
+	y = y0 << 10;
+	if (dx < 0) {
+		dx = - dx;
+	}
+	if (dy < 0) {
+		dy = - dy;
+	}
+	if (dx >= dy) {
+		len = dx + 1;
+		if (x0 > x1) {
+			dx = -1024;
+		} else {
+			dx =  1024;
+		}
+		if (y0 <= y1) {
+			dy = ((y1 - y0 + 1) << 10) / len;
+		} else {
+			dy = ((y1 - y0 - 1) << 10) / len;
+		}
+	} else {
+		len = dy + 1;
+		if (y0 > y1) {
+			dy = -1024;
+		} else {
+			dy =  1024;
+		}
+		if (x0 <= x1) {
+			dx = ((x1 - x0 + 1) << 10) / len;
+		} else {
+			dx = ((x1 - x0 - 1) << 10) / len;
+		}
+	}
+
+	for (i = 0; i < len; i++) {
+		sht->buf[(y >> 10) * sht->bxsize + (x >> 10)] = col;
+		x += dx;
+		y += dy;
+	}
+
+	return;
+}
diff --git a/23_day/lines.c b/23_day/lines.c
new file mode 100644
index 0000000..8cef008
--- /dev/null
+++ b/23_day/lines.c
@@ -0,0 +1,21 @@
+int api_openwin(char *buf, int xsiz, int ysiz, int col_inv, char *title);
+void api_initmalloc(void);
+char *api_malloc(int size);
+void api_refreshwin(int win, int x0, int y0, int x1, int y1);
+void api_linewin(int win, int x0, int y0, int x1, int y1, int col);
+void api_end(void);
+
+void HariMain(void)
+{
+	char *buf;
+	int win, i;
+	api_initmalloc();
+	buf = api_malloc(160 * 100);
+	win = api_openwin(buf, 160, 100, -1, "lines");
+	for (i = 0; i < 8; i++) {
+		api_linewin(win + 1,  8, 26, 77, i * 9 + 26, i);
+		api_linewin(win + 1, 88, 26, i * 9 + 88, 89, i);
+	}
+	api_refreshwin(win,  6, 26, 154, 90);
+	api_end();
+}