The politeness level of 辞書形(ある／する) in replacement of ます form


こんにちは！ I'm just a beginner in Japanese (started my Japanese self-study from
this March) but now I'm working in a Japanese company in Tokyo. Since most
people in my company can't really speak English, I have no choice but to use
Japanese for my daily conversation. Until now I can somehow manage basic
conversations with my co-workers, but I know my Japanese is very beginner-
level. I follow the rule to use formal Japanese (ます/です) instead of (ある/する)
mostly all the time to avoid being impolite. I know it makes my Japanese sound
unnatural/strange but I think it's a safe choice, at least in the workplace
environment. But the more I'm familiar with the language, the more I feel the
need to use less such honorifics. I try to listen to others' conversations to
see if ある/する is used by juniors to seniors or not, and they do use it, much
more than ます form, even with the boss. I find it so tiring to go with such
sentences like: 「昨日は大阪に行きましたけど、雨でしたから出かけなかったです。」 Just for example, how would
you guys make the above sentence sound "more natural"? Can I say like
「昨日大阪に行ったけど、雨だったから出かけなかったです！」when I talk to my boss? I really need more time
to be able to "sense" the language and its politeness, before that よろしくお願いします！




Usually you should use です/ます only at the end of the sentence.  
In the middle of the sentence you can use informal tense (ある/する). So you can
say:  
昨日大阪に行ったけど、雨だったから出かけませんでした！

It is very difficult for foreigners to know when to drop politeness and be
informal, especially if you are talking to your boss or someone superior.  
It is never a bad thing to be over-polite, while making a mistake and being
rude can get into trouble.




Usually you should use です/ます only at the end of the sentence.  
In the middle of the sentence you can use informal tense (ある/する). So you can
say:  
昨日大阪に行ったけど、雨だったから出かけませんでした！

It is very difficult for foreigners to know when to drop politeness and be
informal, especially if you are talking to your boss or someone superior.  
It is never a bad thing to be over-polite, while making a mistake and being
rude can get into trouble.

