Deferential and Polite Speech level

The Korean language is very specific and heirarchial when it comes to the level of speech. There are certain rules that apply depending on one's status and/or age, and the situation. However, for the language learners, choosing an appropriate speech level to use is challenging and needs deep understanding of the Korean culture.

The deferential and polite speech levels have their own uses, although Koreans frequently use both in formal conversational settings. One most common scenario is when meeting a person for the first time, introducing oneself in deferential, and after introductions, the rest of the conversation can be in polite speech level.

Deferential speech level is used in public and/or formal communication settings(broadcasting, public speech, business-related meetings, conference presentations, etc.). It may be declarative,  interrogative, imperative and propositive.

Declarative statements in deferential speech level endings would be in two forms:
    ~습니다 is used when the stem ends in a consonant. 
    먹다 which is the plain form for "to eat" will be 먹습니다 in deferential form.

    ~ㅂ니다 is used when the stem ends in a consonant.
    가다 as in "to go" takes the form 갑니다 in deferential speech.

Interrogative statements, or statements of questions, also takes two forms just like the declarative statement. 
    ~습니까 for consonant-ending stems, and
    ~ㅂ니까 for vowel-ending stems

For commanding, the imperative form is used, also in two forms.
    ~으십시오 for stems ending in consonants, and
    ~십시오 for vowels

Propositive statement is used for requesting/suggesting. It may be translated as "Let us (do)" in English. It also takes two forms:
    ~으십시다 for consonant-ending stems, and