Which is more formal/polite: 大いに or ずいぶん?


I know とても is not very formal, but what about ずいぶん and 大いに? Are ずいぶん and 大いに
interchangeable, and if so, which is more formal?




What is formal in your mind?

Suppose the meeting room is a mess and you want to have it clean. The
following is the e-mail message from you to a person in the General Affairs
Department.

> "会議室がとても汚れています。11時までに、清掃をお願いします。" This is the best and most popular (and
> formal) expression on business.
>
> "会議室がずいぶん汚れています。・・・" This one is also OK.
>
> "会議室が大{おお}いに汚れています。・・・" This one is acceptable but "おおいに" is generally for
> the expression of an emotion. I wouldn't use it for this situation.
>
> "会議室が非常{ひじょう}に汚れています。・・・" The word "非常に" is versatile. It's used widely. I
> can recommend the use of "非常に" for any situation without using set phrases.
>
> "非常に" と言う言い方は、非常に広く使われます。

The common expressions,

> Preceding sentence: "とてもご無沙汰しております" Long time no see. (I'm not sure but
> "とても" in English here can be "very"? Very long time no see.???)

"おおいに" is rather suitable for the expression of feeling.

> "私は、その素晴らしい演奏に、大いに感動した" I was greatly moved by the performance.

