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Eventually, while reading, the user might find a sentence that he has trouble understanding, either because it contains some vocabulary he doesn't remember, or uses some grammatical construction he doesn't understand. In the event that it's some particular word that the user doesn't understand (in our scenario with Joe, りんご), he can expand out the "vocabulary" accordian menu, where he will find all vocab words used in the sentence, their romanizations (ringo), and their definitions . There are also "prioritize" and "deprioritize" buttons for each vocab word, which will be explained later. Alternatively, Joe can hover over the word りんご, at which point the mouse cursor will change shape to indicate a clickability affordance, and then Joe will click the word. This will cause the Vocab accordion menu to be expanded, and りんご and the romanization (ringo) and definition (apple) will become highlighted. There is also a Grammar accordian menu, which can be expanded and will list the grammatical constructs that this sentence uses, and again, there are "prioritize" and "deprioritize" buttons next to thesedeprioritize" buttons next to these.
The user would click prioritize on a vocab or grammar item if he wants to see more sentences of that sort (because he wants to practice reading more sentences that use that particular vocab or grammar), and deprioritize if he doesn't want to see sentences that use that vocab item or grammatical pattern. If the user clicks on prioritize for some vocab word or grammatical pattern, then among the sentences later in the list (which haven't yet been read), the ones that use the vocab or grammar that the user wants to prioritize, will be moved up and injected immediately below the sentence that the user just read (the sentences associated with the accordian menu from which the "prioritize"/deprioritize button was clicked). That way, the next sentences that the user reads will all use the particular grammatical pattern that was prioritized. If the user clicks on deprioritize, then later sentences using that grammatical pattern will be moved to the end of the list, so that the user will see those only after having read all other sentences.
If Joe wants to see the entire sentence romanized, he can expand the "Show romanization" accordian menu. Likewise, if Joe wants to have the English translation of a sentence displayed, he can expand the "Show English translation" accordian menu. If Joe does not understand some grammatical aspect of the sentence, or simply wants more practice with a grammatical form (in the scenario, the -tai verb conjugation), he can expand the Grammar accordian menu. Here, he will find the listing of grammatical aspects that are used in this sentence. Similarly to the Vocab accordian menu, there is a "more sentences" link that, if clicked, will open a new tab displaying only sentences that use that , and he can press "prioritize" on "-tai verb conjugation" so that the sentences using that grammar get moved up to where he is reading at, so that the next sentences he reads utilize the grammatical pattern.
If Joe encounters a sentence whose grammar patterns listed are incorrect, then he can expand the accordian menu, and click the "edit" button. Here, he can remove any categories that are incorrect (or add any that need to be added), and click "done editing" to save changes.
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