diff --git a/time_api.py b/time_api.py
index 3e2c546..9aa324d 100644
--- a/time_api.py
+++ b/time_api.py
@@ -43,7 +43,7 @@ def get_utc_beginning(utc_time: datetime):
     '''
     return utc_time.replace(hour=0, minute=0, second=0, microsecond=0)
 
-def get_utc_after(utc_time: datetime, hours: float, seconds: float):
+def get_utc_after(utc_time: datetime, hours: float=0.0, seconds: float=0.0):
     '''
     获取 utc 时间后面的一个时间点
     '''