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tamnd's digital brain — notes, problems, research
43815 notes
HSK 4 | noun | the background or context of a situation
Core Sindarin verbs with present, past, and future forms — organized by category for practical composition.
Learn 〜として (as, in the capacity of) — the N3 pattern for expressing roles, identities, functions, and premises.
HSK 3 | noun | nurse — medical professional who cares for patients
N1 grammar pattern 〜に至って(は): expressing 'now that it has come to ~, upon reaching this extreme point, at this point finally.'
Master four essential N3 formal conjunctions: 〜において/〜における (in/at), 〜に対して/〜に対する (toward/against), 〜にとって (for/from the perspective of), and 〜として (as/in the capacity of).
HSK 1 | measure word | classifier for chunks, pieces, and Chinese yuan
HSK 4 | verb | to participate, to join, to attend
Learn Chinese family vocabulary, how to express possession with 的, and how to talk about what you have using 有.
HSK 5 | verb | to prompt; to cause; to drive someone to do something
HSK 3 | adjective | at a small height or below a standard level
HSK 1 | pronoun/determiner | interrogative asking for selection among options
HSK 3 | noun | a goal, target, or objective to aim for
HSK 3 | noun / adjective | major field of study; specialized skill or knowledge
HSK 5 | noun | an economic, practical, or personal need or demand for something
HSK 4 | phrase | it is necessary; there is a need
HSK 2 | adjective/noun | incorrect; a mistake or error
前 (zen/mae): before. JLPT N5 kanji.
HSK 3 | verb / noun | to plan, intend to do something; a plan or intention
Learn 〜さえ〜ば (if only ~, as long as ~) — the N3 conditional expressing a single minimal sufficient condition.
HSK 3 | adjective | strange, odd, weird — outside the normal or expected
N1 grammar pattern 〜ものを expressing regret about an unrealised alternative or reproach toward someone who failed to do something they should have. Literary and formal register.
HSK 4 | verb | experiencing sudden surprise or shock
HSK 4 | noun | what is needed or wanted, especially in an economic or practical sense
Learn how to use 〜に先立って (ni sakidatte) to express 'prior to' or 'before' when an action precedes an important event. Includes structure, nuance, examples, and comparisons.
Master reference for all Sindarin verb conjugation: all 12 verb classes, all tenses/moods, all 9 persons — with full tables for model verbs and notes on scholarly disagreements.
HSK 2 | noun | a business company or corporation
Complete JLPT N1 vocabulary reference: ~4,000 new words beyond N2 covering academic, literary, political, legal, medical, and financial Japanese with readings, meanings, and usage contexts.
HSK 4 | verb / noun | to report; to brief; a report
駅 (station): 14 strokes, JLPT N5. On: エキ. Kun: none.
HSK 5 | noun | an unfair preconceived opinion not based on reason or experience
HSK 5 | verb | to value highly and make good use of; to cherish
Sindarin relative pronoun i, relative clause structures, expressing uncertainty and probability, and the particle ma for questions and possibility.
HSK 5 | noun | systematic study or framework of methods used in a discipline
HSK 4 | conjunction | a formal connector meaning however or nevertheless
HSK 5 | verb | deliberate or observed reduction in scope, size, or gap
Complete N4 exam prep: format guide, 25 vocabulary questions, 25 grammar questions, reading passages with questions, listening scenarios, 60-day study plan, and N5→N4 pitfall guide.
HSK 5 | noun/verb | a hesitating worry or reservation that holds one back from acting
Complete N3 exam preparation guide: test format, question type breakdowns, 90-day study plan from N4, most-confusable grammar pairs, kanji reading drills, and test-day strategies.
HSK 1 | noun | a calendar year; also used in age and duration expressions
HSK 3 | verb | to mistakenly believe something to be true
HSK 3 | grammar pattern | softens a comparative or evaluative statement with 'a bit'
HSK 1 | greeting phrase | standard informal greeting for one person
HSK 5 | n | the art of effective language use; a rhetorical figure or device
We are given a list of people, each with a first name and a last name. For each person, we have the freedom to choose either their first or last name as a handle.
We have apples numbered from 1 to n. We want to create as many disjoint pairs as possible such that the two numbers in each pair have greatest common divisor greater than 1. Each apple can appear in at most one pair.
HSK 2 | verb | to communicate information to someone
HSK 5 | verb / noun | to embody; to give expression to
HSK 3 | verb / noun | to rent, to hire; rent, rental fee
HSK 5 | noun | the average height of the ocean surface used as a reference point
Complete JLPT N5 grammar reference: all ~100 grammar patterns with structure formulas, usage explanations, example sentences (Japanese + romaji + English), and notes on common mistakes.
HSK 5 | noun | bond; debenture; fixed-income debt security
HSK 3 | noun/adj | the system of production and consumption; economical
HSK 1 | noun/verb | employment, labor; to be employed or carry out a task
HSK 1 | greeting phrase | reassures someone after an apology
HSK 4 | preposition / noun | using something as a foundation or source
Sindarin vowel elision: when final and initial vowels contract, apostrophe usage, elision in poetry and prose, and the famous Elvish examples from Tolkien's texts.
HSK 4 | verb | to give special weight or importance to a point
HSK 6 | verb | to sort through and organize systematically; to untangle
HSK 5 | noun | cost; production cost; the amount spent to produce or achieve something
HSK 5 | adjective | rigorous; meticulous; careful and thorough
HSK 5 | verb / noun | to cooperate, to collaborate; cooperation, collaboration
HSK 4 | preposition | indicating the object of an action or attitude
来 (rai/ku-ru): come. JLPT N5 kanji.
We are given a set of points on an infinite 2D grid, representing planets in a "meta-universe." The goal is to repeatedly split the set of planets along empty rows or columns that completely separate the set into two non-empty subsets, each lying on one side of the row or column.
HSK 1 | adjective | new, fresh, modern
前 (before, front): 9 strokes, JLPT N5. On: ゼン. Kun: まえ.
HSK 3 | verb | to describe, to depict, to portray in writing or speech
HSK 2 | noun | any watercraft, from a small rowboat to a large ship
HSK 4 | grammar pattern | presenting two contrasting or complementary aspects
Learn to describe the weather and seasons, using impersonal verbs and the conjunction ĉar.
HSK 1 | verb | to listen to or hear something
HSK 3 | noun | temperature — measurable degree of heat or cold
HSK 1 | noun | a number or code; the colloquial word for a day of the month
HSK 4 | noun | a model, template, or small-scale replica
Handle phone calls, send messages, and communicate digitally in Chinese with confidence.
HSK 2 | preposition | in order to, for the purpose of
HSK 5 | noun | background, backdrop, context, personal connections
HSK 4 | noun | doctor, physician
HSK 5 | noun/verb | to export goods; an exit or way out
HSK 3 | noun | the reasoning or principle behind something
JLPT N4 kanji 雪 — readings, vocabulary, stroke order, mnemonic, and common confusion pairs.
JLPT N4 kanji 社 — readings, vocabulary, stroke order, mnemonic, and common confusion pairs.
HSK 5 | noun | innate ability or formal qualification for a role
HSK 4 | adverb | expressing a combined total
HSK 3 | verb | to feel deep gratitude toward someone
HSK 6 | adj/noun | organized and comprehensive; a structured system
HSK 5 | noun | distinctive feature or characteristic that identifies something
HSK 4 | verb | to refuse, to reject, to decline
HSK 5 | noun | a formally concluded and ratified agreement between states
HSK 4 | verb | to present or show something to others
HSK 4 | verb | to clearly express or demonstrate something
HSK 4 | n/v | a successful outcome in a contest or struggle
HSK 3 | noun | colleague, coworker — someone who works at the same place
HSK 3 | noun | email, electronic mail message
N1 grammar: classical auxiliary べし expressing obligation/certainty, and its negative form べからず (must not). Appears in laws, school rules, mottos, and literary contexts.
HSK 3 | verb | to come into view or to happen for the first time
Best websites for learning and researching Sindarin: grammar references, tools, encyclopedias, and specialized resources.
HSK 1 | verb phrase | to make a phone call
HSK 3 | adjective | putting in consistent hard work and effort