-(으)ㄹ 테니까
since (I will / it will probably) …
Level 3 · Connective
Explanation
The first clause is the speaker's intention (first person) or a guess, serving as the reason for a suggestion or command. Vowel or ㄹ stems take ㄹ 테니까, consonant stems 을 테니까.
Examples
제가 표를 살 테니까 여기서 기다리세요.
I'll buy the tickets, so wait here.
길이 막힐 테니까 지하철을 타세요.
The roads will be jammed, so take the subway.
많이 피곤할 테니까 푹 쉬어요.
You must be tired, so get some rest.
TOPIK note
TOPIK II Listening 4–12; Reading 1–2.