A - Telling the time
Telling the time is relatively easy in Korean. The only real difficulty is to keep in mind that hours are expressed in Korean numbers while minutes are expressed in Sino-Korean numbers.
After the hour, the equivalent to "o'clock" - 시 is used and 분 indicates the minutes.
한 시 One o'clock
두 시 삼십 분 Two thirty (minutes)
여섯 시 이십 분 Six twenty (minutes)
B - From... to...
To express the starting and length of an action, we will use the pair "...부터" + "...까지". Unlike English, these particles follow the periods they define.
여덟 시 부터 열한 시 까지 도서관에 공부해요.
C - Verbal suffix -(으)ㅂ시다
This verbal suffix expresses an invitation to a common action. After a root ending with a vowel, -ㅂ시다 will be used, and after a root ending with a consonant, -읍시다 will be used.
만나다 + ㅂ시다 = 만납시다. Let's meet.
가다 + ㅂ시다 = 갑시다. Let's go.
먹다 + 읍시다 = 먹읍시다. Let's eat.
D - Too, also (도)
The particle 도 means "too" or "also" but unlike the English word, it is not an adverb. It will be used instead of other particles. For example:
프랑스어는 어려워요. 한국어도 어려워요.
E - Express an action taking place -고 있다
In English, in order to express an action taking place, one will use the present progressive. In Korean, one will take the root of the verb and add to it the suffix "-고 있다" (in all cases, whether the root ends with a vowel or a consonant).
태호는 먹고 있어요. Tae-ho is eating
저도 공부하고 있어요. I am also eating
Transation of the texts
Kim Tae-ho: Sue, are you free this evening?
Sue: (I) have an exam tomorrow. This is why I am a bit busy today.
Kim Tae-ho: When will your exam be over?
Sue: It will be over at 10 o'clock.
Kim Tae-ho: So let's meet at twelve and go to the canteen.
Sue: OK (good).
Lee Hyeon-ae: John, what have you been doing lately?
John: Studying. Korean is very difficult, but really interesting. This is why I am studying it seriously.
Lee Hyeon-ae: Yes, (I) will soon have a literature exam. This is why I am also studying seriously.
John: OK (good). See you next time!