diff --git a/rt-thread-version/rt-thread-standard/programming-manual/device/i2c/i2c.md b/rt-thread-version/rt-thread-standard/programming-manual/device/i2c/i2c.md
index eb83a305b019cb4369bb068bbc760523dec252eb..8e518bd625853bc3eb6065152254382f5425df27 100644
--- a/rt-thread-version/rt-thread-standard/programming-manual/device/i2c/i2c.md
+++ b/rt-thread-version/rt-thread-standard/programming-manual/device/i2c/i2c.md
@@ -187,7 +187,7 @@ static rt_err_t write_reg(struct rt_i2c_bus_device *bus, rt_uint8_t reg, rt_uint
     {
         buf[1] = data[0];
         buf[2] = data[1];
-        buf_size = 3
+        buf_size = 3;
     }
 
     msgs.addr = AHT10_ADDR;