"I will be absent for today's lesson." 1. 저 오늘 레슨 못 할 거예요. (general and vague) 2. 저 오늘 레슨에 못 갈 거예요. (if the speaker usually goes to the place of a lesson) 3. 저 오늘 레슨에 참석(하지) 못할 거예요. (if the lesson has other participants so that it will still take place without the speaker)