How to enter/leave someone's house politely in Japanese?

When entering say おじゃまします (ojama shimasu)... entering When exiting say おじゃましました (ojama shimashita)... leaving Visit www.japanese999.com for more detail.

Instructions

Difficulty: Moderately Easy

1. Open a door and say
   
   おじゃまします (ojama shimasu)
2. Enjoy your time at the house.
3. When leaving say
   
   おじゃましました (ojama shimashita)