Technically we never even got that far. My Latin classes ran behind schedule, only really only finished up the material of Latin II at the end of Latin III. (We moved to block scheduling my Junior year of high school, so you could say it was really just 2 years of Latin at the normal pace although we should have covered twice as much in the longer class periods.) I still got into the Georgia Governors Honors Program in Latin though, which could be taken to mean that I was one of the 15 best Latin scholars in all the high schools in the state, but that is assuming a perfect selection process and ignoring that fact that only 2 students are eligible from each school. When I returned for my senior year of high school I did AP Latin, although normally there is another course before that. There was going to be one other student in the AP class but she changed her mind because of schedule conflicts, and was a year younger anyway so ended up taking it the text year when there was a class of 3. Anyway, it was basically independent study. The teacher gave me the book containing the first half of the Aeneid at the start of the first semester, although AP Latin was a second semester class. She did not tell me specifically what to translate, so I assumed I had to translate it all. It was slow going at first, but as i assumed I had a lot ahead of me I focused on it, brought it with me to work on at lunch every day, and by the end of the first semester I had translated a little more than a book and a half. I then lost all I had written at the start of the second semester, and had to start over. I had gotten better at it by then though, and so managed to redo everything from the first semester in 2 weeks. I then finished the last of the assigned translations on valentines day, and just goofed off in that class for the rest of the semester. I still managed to get a 5 out of 5 on the Latin (Virgil) AP exam though, and considered it the easiest AP exam I ever took. Georgia Tech does not have Latin so I have taken no courses in it since 2006, but I did get a Vulgate which I read at least once a week at church.
We used the Cambridge Series, which I hear is not as good as Ecce Romani. (Before starting Latin I also got an old and battered copy of what I hear is the best of all the Latin textbooks, which I would skim occasionally on my own.) Cambridge did use gerundives a couple times as early as the first book, but did not explain them until the third book. They always had gloss translations, but as a rule I never trust glosses. They are rarely literal, and only serve to hide the idiomatic workings of the tongue. Whereas most students did not bother trying to figure out what such phrases meant when there was a gloss, I always insisted on trying to figure out for myself what it meant, from context if not researching on my own. The last thing we learned in Latin III was how to use a basic gerundive, but I'd figured it out long before then and understood them better than the teacher. I love gerundives, and although it can be really awkward to try to translate them in some contexts they seem to be especially eloquent and easy to understand.
Our class never got to Future Perfect Indicative or Perfect Subjunctive, except maybe spending 2 minutes talking about them on the last day of class They aren't that hard to understand, but I still never really know how to translate them without sounding extremely awkward. It does not help that they are the same except in first person either.