The workshop was highly profitable in terms of gaining practical skills.

profitable 是形容词，由名词 profit（利润、收益）加上后缀 -able（能够...的）构成，字面意思是"能够带来利润的"，引申为"有益的、有利可图的"。在句中表示"在获得实用技能方面很有帮助/很有收获"。