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readme.md

@@ -224,7 +224,7 @@ class MyModelQuery extends ActiveQuery
                 $bitFlagsConditions[] = "$bitFlag & $mask = $res";
             }
         }
-        return new Expression(implode('and', $bitFlagsConditions));
+        return new Expression(implode(' and ', $bitFlagsConditions));
     }
 }
 ```