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HSK 3 | grammar pattern | expresses whether an action can or cannot achieve its result

A comprehensive guide to UEA, TEJO, Pasporta Servo, Esperanto's international institutional life, official exams, and the language of Esperanto organizations.

HSK 3 | noun | an obligation one is accountable for; a duty that must be fulfilled

HSK 1 | noun | doctor, physician

HSK 3 | noun / verb | a plan or program; to plan something in advance

Learn 〜こそ and 〜だからこそ to place emphatic focus on a specific element — 'it is precisely X' and 'precisely because of X.'

HSK 2 | verb phrase | to make or place a telephone call

HSK 3 | noun / verb | a link between people or things; also in set phrases

HSK 3 | noun | a location, area, or region

HSK 5 | verb / noun | to inspire, to enlighten; inspiration, enlightenment

HSK 3 | noun | class, classroom group; work shift; scheduled service

HSK 5 | verb | to envy, to admire, to look up to with longing

HSK 1 | particle | softens suggestions and expresses tentative assumptions

HSK 3 | noun / adverb | time reference word for events before a stated point

HSK 5 | noun | the principles of valid reasoning or the internal consistency of an argument

Learn how to use 〜てしかたがない (te shikataganai) to express uncontrollable feelings or irresistible urges — 'can't help but ~; irresistibly ~.' Includes structure, nuance, examples, and comparisons.

Sindarin time vocabulary: days, months, seasons, the Elvish calendar (Reckoning of Rivendell), time expressions, and attested Elvish date references.

HSK 4 | adjective / noun | patient; patience

HSK 1 | adverb / adjective | intensifier meaning really or genuinely

HSK 3 | preposition | about, concerning, regarding — introduces the topic of a statement

The sequence in this problem comes from counting lattice points inside a growing hexagon on a hexagonal grid. Instead of having to construct the hexagon or count points manually, the problem already gives the formula for the sequence: $$Hn = 3 cdot n cdot (n+1) + 1$$ The input…

HSK 5 | verb / adjective / noun | to deny; to negate; negative

高 (kou/taka-i): tall. JLPT N5 kanji.

HSK 4 | noun | a geographical or administrative area

HSK 4 | verb | to clearly express or demonstrate something

HSK 4 | verb | to take advantage of something for a purpose

休 (kyuu/yasu-mu): rest. JLPT N5 kanji.

HSK 3 | noun | the way something is facing or moving

HSK 3 | adjective/verb | feeling nervous or embarrassed in social situations

HSK 5 | verb/noun | to report (news); a news report or coverage

HSK 1 | noun | a number or code; the colloquial word for a day of the month

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

HSK 3 | adverb / expression | expresses compulsion arising from circumstances, not personal will

気 (spirit, mood): 6 strokes, JLPT N5. On: キ、ケ. Kun: none.

HSK 4 | noun/verb | taking action in advance to stop something bad from happening

HSK 3 | adverb | singles out one item from a group as deserving special emphasis

Complete N3 vocabulary reference: ~2,250 new words beyond N4, organized by semantic domain. Abstract nouns, workplace terms, academic vocabulary, emotional states, and more.

HSK 1 | noun | dog

HSK 3 | verb | to hang something up or be suspended

HSK 5 | noun | contract, written agreement

Learn the formal conjunctive particle 〜において (in, at — domain marker) and its attributive form 〜における, essential for N3 reading and formal written Japanese.

HSK 5 | adjective | easily affected, responsive, or requiring careful handling

HSK 5 | noun phrase | content recommendation driven by algorithms

HSK 3 | adverb | describes the normal or typical state of affairs

HSK 5 | noun | political system based on concentrated authority and limited freedoms

Learn 〜てからというもの to express a fundamental, sustained change that began at a specific turning point.

HSK 5 | adjective/verb | thorough; penetrating deeply into a topic or place

Master the full range of Esperanto comic expression, from morphological puns and satirical register to the tradition of Esperanto folk humor.

Consolidate all B1 grammar and vocabulary, review CEFR B1 can-do statements for Esperanto, and prepare for the B2 level.

海 (kai/umi): sea. JLPT N5 kanji.

HSK 4 | verb / noun | to invite; an invitation

Intermediate Sindarin: all 5 mutations, the full verb system, Tengwar writing, and composing original sentences — goals and resources for 100–300 hours.

HSK 5 | verb/noun | to discuss and reach agreement through mutual consultation

HSK 6 | verb | to test and confirm the truth or validity of something

HSK 3 | verb/noun | a sensation or the act of feeling

Learn food and drink vocabulary and how to order, express preferences, and use the infinitive with modal verbs like voli and ŝati.

HSK 3 | verb / preposition | to pass through or by; after going through a process

HSK 5 | verb/noun | to have an effect on someone or something; the effect produced

HSK 4 | grammar pattern | expressing preference by rejecting one option in favor of another

HSK 4 | noun | science and technology as a combined field

HSK 3 | noun | experience gained through practice or living, not academic knowledge

Discuss health and medical topics using advanced 被 constructions and 受 + emotional/physical state at B1 level.

HSK 1 | verb | to see, to catch sight of

Complete HSK 6 vocabulary reference: approximately 1,800 new words at C1 level, organized by semantic category with pinyin, English, part of speech, and usage notes.

HSK 5 | noun | a computer or system that provides data or services to other computers over a network

HSK 3 | adverb | reveals the true situation, often correcting a misconception

HSK 3 | noun | fortune; chance; whether things go well or badly

HSK 3 | adverb | marks a turning point after which everything that follows is different

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 | the color black; also dark (absence of light)

HSK 5 | adjective | resistant to change; preferring traditional values

HSK 2 | verb | to agree with, to consent to, to approve

Essential Japanese vocabulary for rooms, furniture, household items, chores, daily routines. N1 level reference with readings, romaji, and examples.

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

HSK 4 | verb / noun | giving assistance, backing, or resources to someone or something

The language of Chinese economic analysis — 就...而言 in economic framing, macroeconomic and microeconomic vocabulary, and the discourse of policy economics

HSK 3 | verb/noun | an expression of friendly acknowledgment or well-wishes

HSK 1 | noun | student, pupil

HSK 3 | verb | to continue or keep doing something

見 (ken/mi-ru): see. JLPT N5 kanji.

HSK 3 | conjunction | introduces the single condition that is the only exception to a rule or the only way an outcome can occur

HSK 5 | noun | the level of openness, clarity, or accountability in a system or process

Language for navigating cultural difference — expressions for cultural contrast, conflict, fusion, and the pragmatics of intercultural interaction at C1 level

We have two walls represented by sequences of tower heights. The bears' wall contains n towers, while Horace's wall contains w towers. Horace is allowed to shift his entire wall vertically by any amount.

HSK 3 | noun | a dictionary, especially one that explains words and their meanings

HSK 3 | noun | task, mission, assignment — something assigned or required to be done

HSK 4 | verb / noun | to think deeply; to ponder; reflection

Creating Sindarin personal names: masculine and feminine name elements, patronymics, epithets, and the naming traditions of Tolkien's Elves.

HSK 3 | adjective / noun | dangerous, risky; danger, risk

HSK 4 | verb/noun | using words to portray something in detail

HSK 4 | verb/noun | a face-to-face evaluation or job interview

HSK 5 | adjective/adverb | going all the way; leaving nothing incomplete

HSK 4 | verb | to estimate or anticipate a future outcome

HSK 1 | pronoun | second-person plural pronoun

HSK 1 | conjunction | introduces a reason or cause, paired with 所以

HSK 1 | noun | hospital, medical facility

HSK 1 | adverb | indicates earliness, immediacy, or that something happens sooner than expected

HSK 4 | n/v | a successful outcome in a contest or struggle

HSK 4 | adjective | diligent, hardworking