Question

두세 잔 하니까 모두 기분이 좋아졌어요 As a causative marker, -(으)니까 links the reason-clause with the main clause. In such sentences, the action or state denoted in the main clause is conditioned by the reason expressed in the -(으)니까-clause.-(으)니까 is used to express a subjective reasoning based on the speaker's own assessment. Causes and their natural effects cannot be connected by -(으)니까; -아/어서 is used in such cases. The subjective reasoning expressed by -(으)니까 makes the pattern usable in imperative and propositive sentences.-(으)니까 is also used when communicating an inference based on the speaker's assumption.

Accepted Answer

After a few drinks, everyone was in a good mood

Front	두세 잔 하니까 모두 기분이 좋아졌어요
Back	After a few drinks, everyone was in a good mood
Notes	As a causative marker, -(으)니까 links the reason-clause with the main clause. In such sentences, the action or state denoted in the main clause is conditioned by the reason expressed in the -(으)니까-clause. -(으)니까 is used to express a subjective reasoning based on the speaker's own assessment. Causes and their natural effects cannot be connected by -(으)니까; -아/어서 is used in such cases. The subjective reasoning expressed by -(으)니까 makes the pattern usable in imperative and propositive sentences. -(으)니까 is also used when communicating an inference based on the speaker's assumption.

으)니까 Main Expressed Subjective Reasoning Based Speaker's 두세