Klingon is very different from English and at the beginning stages is at least as hard as any language. But as you get used to the differences, it gets easier. If you have not been reading the Tips & Notes, you will find it much easier if you do read them. If you have read them and have questions, please be specific in your question so we can figure out where the confusion is.
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/, either from your mobile device or from a computer. When you click on a Skill, it will expand to reveal a Start button and a light bulb. If you click on the light bulb it will reveal the Tips & Notes and give you a detailed explanation of the grammar that is introduced in that Skill.
This course does not have audio yet.
Please see https://forum.duolingo.com/comment/26778885 for a list of this and other known issues this course has.
Also, personally I recommend not using the Android app to learn Klingon, as it does not easily give access to the lesson tips and notes which explain the grammar.
Instead, I would suggest that you use the website version on https://www.duolingo.com/ . There, tips and notes are available by clicking on the little lightbulb icon next to the Start button after selecting a lesson unit.
Welcome to the fun of translating! Klingon can sometimes be a more compact language. It puts meaning into every syllable and has very few multiple syllable roots. If we count syllables instead, we get 6 Klingon syllables. Comparing that to English words, we get 6 English words. As you learn Klingon you will find sentences that are much more disparate than that!
The meanings of the prefixes bI- and Da- are explained in the tips and notes for this unit.
If you are using the website, you can access the tips and notes by clicking on the little lightbulb next to the Start button after selecting a lesson unit:
Have a look in the "Verbs" section.
If you are using a mobile app, you may not have access to the tips and notes, which makes it more frustrating and confusing to learn Klingon than it needs to be. Consider switching to the website version, at least to open and read the tips and notes before starting a lesson.
If there is something unclear in the tips and notes or something you do not understand about this sentence after reading the tips and notes, please do reply with what you found missing or confusing.
Also, please pay attention to commas in this unit. Just as "Let's eat, Grandma!" means something quite different from "Let's eat Grandma!" in English, so also in Klingon, something like torgh Dayaj'a'? and torgh, Dayaj'a'? mean quite different things.
Because mara is the thing directly before the verb and so must be the object (the thing being understood) and torgh is separated from the sentence (in writing by a comma and in speech by a pause and or change in tone) and so is just calling out someone's name to get their attention.
The Duolingo administration decided not to provide audio for the Klingon course at first (which has been true for a few of their more atypical languages). The Contributors and Moderators would love to add it and Duolingo is working on a method that might allow us to do it, but even when they add the ability, it's going to take us a long time to add audio for many of the sentences.
There is a Skill a little bit into the course which teaches the names of the Klingon letters and has a description of the pronunciations in the Tips & Notes, however, that skill also lacks audio. If you want to check out some ideas for learning the pronunciation, check out the thread at: https://forum.duolingo.com/comment/26605745
If you want to read about the other known issues in this course, read the post at: https://forum.duolingo.com/comment/26778885
For a few reasons. Number one is that the Da- prefix on the verb means that the listener is the one doing the action. Dayajbe' means, "you did not understand her".
To say, "Torg did not understand her", we would use the null prefix (in other words, the absent prefix). Torg, the grammatical subject - the one doing the action, would also be placed after the verb. So mara yajbe' torg would be used to mean "Torg did not understand Mara." This would be someone speaking about Torg and Mara rather than directly to them.
Torg, in this exercise, is separated from the sentence by a comma. In this exercise his name is not actually part of the sentence. He is being called before saying the sentence. So now the Da- does, in fact, refer to Torg, but it is because the speaker is actually speaking to him when they say "you".