Comparing "gongfu" and "shijian"

工夫 (gōngfu) and 时间 (shíjiān) are both nouns that can be used to mean “time” and sometimes they can be used interchangeably. 工夫 is used in informal situations, whereas 时间 is used in both informal and informal situations. The uses of 时间 are much wider than 工夫. Only 时间 can be paired with a specific time (10 o’clock, etc.), to describe the general condition of it being early or late in the day, or to discuss time as an abstract concept.

工夫 (gōngfu) 时间 (shíjiān)
Meaning time time, time of the day
Part of Speech noun noun
Formality informal flexible

Note: use 工夫 (gōngfu) to mean time, and not 功夫 (gōngfu).