diff --git a/nemu/src/isa/riscv32/inst.c b/nemu/src/isa/riscv32/inst.c
index 7d7d8e7..a7ad609 100644
--- a/nemu/src/isa/riscv32/inst.c
+++ b/nemu/src/isa/riscv32/inst.c
@@ -67,7 +67,7 @@ static int decode_exec(Decode *s) {
   INSTPAT_START();
   INSTPAT("??????? ????? ????? ??? ????? 01101 11", lui    , U, R(rd) = imm);
   INSTPAT("??????? ????? ????? ??? ????? 00101 11", auipc  , U, R(rd) = s->pc + imm);
-  // INSTPAT("??????? ????? ????? ??? ????? 11011 11", jal,   , J, do_jump(s, rd, imm) );
+  INSTPAT("??????? ????? ????? ??? ????? 11011 11", jal    , J, do_jump(s, rd, imm) );
   INSTPAT("??????? ????? ????? ??? ????? 11001 11", jalr   , I, do_jump(s, rd, imm) );
   INSTPAT("??????? ????? ????? 100 ????? 00000 11", lbu    , I, R(rd) = Mr(src1 + imm, 1));
   INSTPAT("??????? ????? ????? 000 ????? 01000 11", sb     , S, Mw(src1 + imm, 1, src2));