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HSK 4 | verb | to come into view or existence

HSK 4 | verb / noun | setting boundaries on what is allowed or possible

HSK 3 | verb | to enter into marriage

HSK 6 | n | a solemn duty or calling, especially one of great historical or moral significance

HSK 4 | noun | situation; circumstances; condition

HSK 3 | noun | an organization or place of work, also a unit of measurement

HSK 5 | verb/adjective | to relieve someone's worry; feeling comforted or relieved

HSK 2 | noun | a matter, an affair, something to deal with

HSK 5 | noun | a person's point of view or standpoint on an issue

Master the formal grammar patterns used in legal documents, academic writing, and official correspondence, including 〜ものとする, 〜に即して, 〜に反して, 〜をもって, and 〜いかんによらず.

HSK 5 | noun phrase | sustainable development

HSK 3 | determiner | every, each — used before a measure word or time word

金 (kin/kon/kane): gold. JLPT N5 kanji.

HSK 1 | verb | to drink a liquid

Master the hardest N1 exam question type: choosing between near-synonymous grammar patterns. Deep comparison of すら/さえ/でも, ものの/ながらも/けれども, ことなく/ずに/ないで, てならない/てたまらない/てしかたがない, and…

分 (fun/bun/bu/waka-ru): minute. JLPT N5 kanji.

Learn how to use 〜というより (to iu yori) to replace or correct a description with a more accurate one — 'rather than saying ~, it's more ~.' Includes structure, nuance, examples, and comparisons.

HSK 1 | adjective | delicious, tastes good

We are given an $n times n$ matrix where each entry $d[i][j]$ represents the distance between nodes $i$ and $j$. The question asks whether there exists a weighted tree with $n$ nodes such that the distance along the tree between any two nodes exactly matches the corresponding…

HSK 3 | adjective | negative, passive, pessimistic — opposite of 积极

An analytical study of Esperanto's linguistic evolution, the Akademio's role, the Ido schism, native speakers, sociolinguistics, and corpus linguistics.

HSK 5 | noun | a person's or group's point of view or stance on an issue

生活 (せいかつ / seikatsu): daily life, living. N4 level Japanese vocabulary.

HSK 3 | noun | one's particular way of seeing or interpreting something

HSK 4 | noun | the organized body of people sharing a culture and institutions

HSK 3 | adverb / adjective | directly, straight; without an intermediary or detour

HSK 4 | verb | to make changes to improve or correct something

HSK 5 | noun | a set of rules or instructions for solving a problem or performing a computation

HSK 3 | noun / preposition | the space or position in the middle of something

HSK 3 | adverb | once, at one time, formerly — always refers to past experience

HSK 4 | noun | a person who offers help freely without pay

HSK 4 | verb | managing, resolving, or processing a matter

HSK 5 | adjective | extending over a long period or into the distant future

HSK 5 | conjunction | introduces an additional and often stronger reason or argument

先 (sen/saki): before. JLPT N5 kanji.

Learn 〜とは限らない to express that something is not necessarily or universally true, countering general assumptions.

HSK 1 | verb | to hit, to strike, core of many action phrases

HSK 5 | noun | the beliefs, customs, arts, and social institutions of a group; also education and literacy

HSK 5 | noun | cloud computing; internet-based computing services

HSK 1 | noun | taxi, cab

HSK 4 | noun | student, pupil

HSK 5 | noun | the physical components of a computer or device

木 (tree, wood): 4 strokes, JLPT N5. On: モク、ボク. Kun: き、こ.

HSK 4 | verb/noun | to lead or a person in a leadership position

HSK 5 | noun | benefits or services provided to improve well-being

10 structured N1 lessons for advanced learners: classical Japanese roots, authentic text reading, four-character idioms, literary grammar, legal Japanese, academic writing, nuance distinctions, listening, and exam strategy.

HSK 5 | verb/noun | to spread; to disseminate; transmission of information or disease

Complete treatment of Sindarin na- (to be): present nâ, past nant, future natha, imperative no, and predicative adjective construction.

HSK 3 | noun | an interconnected system; the internet

HSK 3 | noun | tour guide, someone who leads tourists

HSK 5 | verb | to set up, establish, or form an organisation or team

Common Sindarin phrases, greetings, and key passages — including A Elbereth Gilthoniel with full word-by-word translation.

Complete reference of the 1,026 Kyoiku kanji (教育漢字) taught in Japanese elementary school grades 1–6, with stroke counts, key readings, and meanings.

HSK 5 | noun | artificial intelligence; AI

HSK 1 | adverb | all, both — applies a statement collectively to all subjects

Learn 〜に沿って and 〜に沿った to express acting in line with plans, policies, or guidelines in formal Japanese.

HSK 4 | adverb/adjective | absolute or absolutely certain

HSK 5 | noun | predicament, difficult situation, dilemma, plight

The game can be viewed as moving through a trie built from the given strings. We start at the root, which represents the empty string. On each turn a player chooses one outgoing edge, corresponding to appending a character.

HSK 3 | noun / verb | success; to succeed, to be successful

Learn 〜に従って (in accordance with / as ~ progresses) — the N3 pattern for expressing compliance with rules and proportional change.

Learn 〜て以来 (ever since ~) — the N3 pattern for expressing a persistent state that has continued uninterrupted since a past event.

HSK 2 | verb/adjective | to get angry, to be angry

Learn everyday Japanese verbs, understand u-verb and ru-verb conjugation, and express present, past, and negative actions using the polite ます form.

HSK 4 | noun / adjective | the modern era or something that is contemporary

HSK 3 | adverb | something happened very recently or barely meets a threshold

Learn to form and use the Esperanto passive voice with esti + participles, agent phrases with de, and the impersonal oni construction.

Master advanced formal conjunctions and particles essential for professional communication, news analysis, and JLPT N2 reading comprehension.

Master five classical Chinese idioms with their full narrative and argumentative contexts, understanding their etymologies and modern usage patterns.

HSK 3 | verb/adjective | to use resources carefully and avoid waste

Move from language learner to active community contributor through writing, teaching, volunteering, hosting, and building online and local Esperanto culture.

HSK 3 | verb | to agree, to consent, to approve

HSK 4 | verb | to cause something to move forward or develop

JLPT N4 kanji 事 — readings, vocabulary, stroke order, mnemonic, and common confusion pairs.

手 (hand): 4 strokes, JLPT N5. On: シュ、ズ. Kun: て.

We are given a sequence of integers arranged in a line, and our goal is to sort them in non-decreasing order by repeatedly performing a single allowed operation: moving the last element of the sequence to the front.

HSK 2 | adjective/preposition | correct or right; also introduces the target of an action

HSK 8 | noun | microprocessor; a single integrated circuit that functions as a CPU

HSK 5 | verb | to promote and spread something admirable, especially cultural or moral values

N1 grammar patterns 〜あっての and 〜あってこそ: expressing that X is an indispensable prerequisite for Y. 〜あってこそ adds emphatic force.

HSK 1 | pronoun | interrogative pronoun for location (standard/southern form)

下 (down, below): 3 strokes, JLPT N5. On: カ、ゲ. Kun: した、さ-がる、くだ-る.

魚 (fish): 11 strokes, JLPT N5. On: ギョ. Kun: さかな、うお.

HSK 5 | adjective/noun | the state of being free from danger or risk

HSK 5 | noun/verb | introducing new ideas, methods, or products; the act of innovation

HSK 5 | verb | to execute; to carry out; to implement a plan, order, or task

HSK 1 | verb | to be aware of, to have knowledge of a fact or situation

晩 (ban/): evening. JLPT N5 kanji.

HSK 5 | verb/noun | to study independently, teach oneself; self-directed learning

Complete JLPT N5 vocabulary list with ~800 words organized by category: nouns, verbs (with て-form and た-form), adjectives, adverbs, particles, question words, and expressions.

HSK 3 | noun | a written piece such as an article or essay

HSK 3 | verb/noun | to plan or organize something

HSK 1 | pronoun | third-person singular pronoun for non-human things

HSK 8 | noun | structural engineering; the branch of civil engineering concerned with load-bearing structures

HSK 2 | measure word | counts complete pieces of written or composed work

HSK 3 | verb / preposition | to pass (an exam); through the means of; by way of

HSK 2 | measure word | counts sections, periods of time, and stretches of things

HSK 1 | verb | to exit, to go out, to come out

Learn to build complex sentences using subordinating conjunctions: ke, ĉar, kvankam, se, kiam, por ke, and indirect questions.