"I do not understand Mara."
Note also the spelling: both the prefixes jI- (subject = I, no object) and vI- (subject = I, object = him/her/it/them) have a capital i, not a small L.
The capital i I is a straight line in the font used on Duolingo (at least on the website), while the small L l has a little curl at the bottom.
An explanation is given in the Tips & Notes, but I know it’s a lot of new information and some details are bound to be difficult to understand or slip through the memory. However, since Duolingo has hidden the Tips & Notes I want to make sure you know about them and where to find them. If you have not been reading the Tips & Notes, I would like to ask that you review those.
If you are doing the course on iOS or Android, you cannot currently access the Tips & Notes through the app. To access the Tips & Notes, you will have to access the course using a web browser at https://www.duolingo.com/. You can still do it on your mobile device, but you will have to use the web browser instead of the app (or you can do it from a computer). When you click on a Skill, it will expand to reveal a Start button and a Tips button.
If you click on the Tips button it will reveal the Tips & Notes and give you a detailed explanation of the grammar that is introduced in that Skill. If you have questions after reading the Tips & Notes for any Skills, we are happy to answer your questions, but many of your questions will probably already be answered in the Tips & Notes.
The tips and notes for this unit are at https://www.duolingo.com/skill/kl/Useful-phrases/tips-and-notes.
I think that the vast majority of learners think Klingon is hard when they start. There are sounds you've never heard and letters that don't sound like you want them too. And all the grammar is mixed up and turned around. It is quite difficult to get your brain used to the different word order of Klingon. The good news is that it's only so hard because it's unfamiliar. The language is actually easy once you get used to it. Stick with it and you'll find it gets easier. And if you aren't reading the Tips & Notes, please go read them. They will help a lot. If you don't know how to find them, I have posted the instructions elsewhere in this Sentence Discussion.