Generally I devote an hour and a half of my day to each lesson to go through the lesson and do all the activities diligently, sometimes this is a bit tight, sometimes there is plenty of time left and I spend the extra time playing around on Duolingo. But I've never failed to finish.
Lesson 3.7 I'm not even close to perfect after an hour and a half. This lesson, introducing irregular verbs ending in IR in all it's complexity, is far too dense for a novice like myself to accomplish in this time and would be far better served being broken up into more bite sized pieces. It feels rushed, and poorly considered. You're giving multiple concepts, cultural nuances, odd conjugating, and more complex use cases for a range of important words used in daily life, and it's frustrating to stumble through this lesson especially when the previous lessons have been accomplishable in the manner of structured learning I already had put in place for this course.
Considered breaking it into at least two separate lessons.