diff --git "a/\347\254\254\345\233\233\347\253\240/4.2.3 \351\222\261\345\214\205\343\200\201\350\264\246\346\210\267\345\222\214\344\272\244\346\230\223\345\212\237\350\203\275.ipynb" "b/\347\254\254\345\233\233\347\253\240/4.2.3 \351\222\261\345\214\205\343\200\201\350\264\246\346\210\267\345\222\214\344\272\244\346\230\223\345\212\237\350\203\275.ipynb"
index 11f7162..c380a85 100644
--- "a/\347\254\254\345\233\233\347\253\240/4.2.3 \351\222\261\345\214\205\343\200\201\350\264\246\346\210\267\345\222\214\344\272\244\346\230\223\345\212\237\350\203\275.ipynb"	
+++ "b/\347\254\254\345\233\233\347\253\240/4.2.3 \351\222\261\345\214\205\343\200\201\350\264\246\346\210\267\345\222\214\344\272\244\346\230\223\345\212\237\350\203\275.ipynb"	
@@ -447,8 +447,8 @@
     "    recipient=tom.address,\n",
     "    amount=0.3\n",
     ")\n",
-    "sig = tom.sign(str(new_transaction))\n",
-    "new_transaction.set_sign(sig, tom.pubkey)"
+    "sig = alice.sign(str(new_transaction))\n",
+    "new_transaction.set_sign(sig, alice.pubkey)"
    ]
   },
   {
@@ -475,7 +475,7 @@
     "    \n",
     "    # 验证交易签名没问题，生成一个新的区块\n",
     "    print(\"验证交易成功\")\n",
-    "    new_block2 = Block(transactions=[new_transaction], prev_hash=\"\")\n",
+    "    new_block2 = Block(transactions=[new_transaction], prev_hash=genesis_block.hash)\n",
     "    print(\"生成新的区块...\")\n",
     "    w2 = ProofOfWork(new_block2, bob)\n",
     "    block = w2.mine()\n",