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Learn to share, support, and disagree with opinions using 觉得, 认为, and related expressions.

Express precise numerical and degree-based comparisons using A是B的N倍, A比B+V得多, and 差不多 at B1 level.

HSK 5 | discourse marker | in summary, to summarise what has been said above

HSK 4 | noun | family member, family

Mastering formal written and spoken Esperanto for business correspondence, academic writing, conference presentations, and professional contexts.

HSK 5 | noun/verb | a hesitating worry or reservation that holds one back from acting

HSK 4 | noun | a specific action taken to achieve a goal or solve a problem

HSK 1 | number | the digit two; used in isolation, ordinals, and compound numbers

花 (flower): 7 strokes, JLPT N5. On: カ. Kun: はな.

HSK 5 | noun | a person who uses a product, service, or system

HSK 4 | noun | thinking; thought; way of thinking

HSK 6 | verb | to officially issue or promulgate laws, regulations, or decrees

HSK 1 | adjective | hot (temperature or weather)

父 (father): 4 strokes, JLPT N5. On: フ. Kun: ちち.

Complete N3 kanji reference: 184 new kanji beyond N4, organized by meaning category. Includes stroke counts, on-yomi, kun-yomi, example words, and tricky reading notes.

HSK 5 | adjective | on the brink of danger or extinction; endangered

土 (earth, soil): 3 strokes, JLPT N5. On: ド、ト. Kun: つち.

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

HSK 5 | verb / noun | to come into existence; the birth or emergence of something

HSK 1 | noun | chair, seat

HSK 4 | verb | to collect, to gather

読 (read): 14 strokes, JLPT N5. On: ドク、トク、トウ. Kun: よ-む.

Learn Esperanto numbers from zero to a million, including ordinals, fractions, and arithmetic expressions.

HSK 5 | noun | the exclusive legal right to reproduce, publish, and sell creative work

HSK 8 | noun | thermodynamics; the branch of physics dealing with heat and energy

HSK 6 | n | the overall pattern, configuration, or situation of affairs; a person's breadth of vision

白 (white): 5 strokes, JLPT N5. On: ハク、ビャク. Kun: しろ、しら、しろ-い.

We are given an array of integers, a[1…n], and a recursive function f(i, j) defined on it. The function essentially accumulates sums along specific paths: the base case is simply f(1, j) = a[j], and for later rows, each f(i, j) is the sum of a[j] plus the minimum of f(i-1…

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

HSK 5 | noun | underlying fundamental principle or law governing operation

HSK 4 | verb/noun | granting official permission or power to someone

HSK 2 | verb/noun | to assist someone; the act of assistance

HSK 4 | verb | the active process of acquiring knowledge or skills

Understand the structure, expectations, and preparation strategies for the KER C2 (Komuna Eŭropa Referenckadro C2) Esperanto examination held at the Universala Kongreso.

HSK 4 | noun | the monetary or intrinsic worth of something

HSK 5 | verb/noun | quantitative increase or growth in numbers

HSK 4 | noun | teacher, instructor

HSK 4 | n/v | the state of not succeeding; to not succeed

HSK 5 | noun | a subject or theme being talked about

日 (nichi/jitsu/hi): sun. JLPT N5 kanji.

HSK 4 | noun | a place or system where goods and services are exchanged

HSK 5 | noun | ethics; ethical principles; moral philosophy

HSK 7 | verb | mechanical or assisted ventilation of the lungs in critical care settings

〜そうだ (appearance): JLPT N4 grammar pattern. Usage, structure, examples, and comparison with similar patterns.

HSK 2 | adjective | describes the absence of dirt or mess

HSK 6 | verb | to interpret and explain the meaning of a text, concept, or phenomenon

Narrate past events fluently using sequence words, duration expressions, frequency adverbs, and past-time framing.

HSK 5 | noun | the exchange of goods and services between parties or nations

HSK 4 | verb/noun | to arrange people or resources into a structured whole; a group with a shared purpose

HSK 1 | verb, adverb | please, to invite, to treat someone

HSK 1 | greeting phrase | asks about someone's wellbeing

月 (getsu/gatsu/tsuki): moon. JLPT N5 kanji.

HSK 3 | noun | the deeper significance or importance of something

高 (kou/taka-i): tall. JLPT N5 kanji.

Sindarin past tense formation: strong past (vowel change + nasal infixion) for primary verbs and weak past (-ant suffix) for A-stem verbs, with all 6 persons.

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

HSK 4 | conjunction | a formal connector meaning however or nevertheless

HSK 5 | noun/verb | a period or process of change from one state to another

HSK 3 | verb | to raise, improve, or enhance a level or standard

安 (an/yasu-i): cheap. JLPT N5 kanji.

HSK 3 | noun | towel, face cloth

HSK 3 | verb + directional complement | to run back to a place away from the speaker

HSK 5 | verb | to research and discuss; to deliberate in a seminar setting

Master the N1 listening section: natural native speed (400+ chars/min), implied meaning, speaker stance inference, pitch accent minimal pairs, note-taking for long monologues, and analysis of five authentic-difficulty listening scripts.

N1 grammar pattern 〜ならでは: expressing exclusivity — something only possible with X, uniquely characteristic of X.

We are given a directed graph where every edge has a weight. We want the longest possible path measured by the number of edges, with one restriction: whenever we move from one edge to the next, the new edge must have a strictly larger weight than the previous one.

HSK 5 | verb | to restrain, contain, or suppress a negative force or trend

HSK 5 | adjective / adverb | existing or occurring generally among all people or in most places

Mastering Chinese financial register: capital markets, corporate finance, and investment discourse.

HSK 4 | n | the Olympic Games, held every four years

HSK 4 | noun / adjective | strategy; strategic

HSK 1 | verb | to run, to jog

HSK 1 | verb | to write characters, text, or content

HSK 3 | verb | to feel at ease; to set one's mind at rest

間 (kan/ken/aida): interval. JLPT N5 kanji.

HSK 1 | verb | to produce speech or language

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

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

HSK 4 | verb / noun / adverb | applying sustained energy and determination

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

Learn family vocabulary and master Esperanto's -in- suffix for feminine forms, ge- prefix for mixed-gender groups, and possessive adjectives.

HSK 5 | noun/adjective | green (colour); eco-friendly, sustainable, clean

HSK 5 | adjective/verb | severely insufficient in supply; a state of dire shortage

HSK 3 | preposition/conjunction | introduces a cause or reason, more formal than 因为

HSK 4 | noun | a positive result obtained through effort

All Sindarin prepositions with their mutation triggers: soft, nasal, and mixed — with worked examples and the dative/genitive constructions.

HSK 6 | verb | to draw conclusions through reasoning from available evidence

We are given an array of n non-negative integers. A group is any non-empty subset of array indices. For a chosen group, we take the bitwise AND of all values at those indices. The task is to count how many non-empty groups have bitwise AND equal to 0.

HSK 1 | noun | chicken egg, egg

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 5 | adjective | considering only one aspect; partial; one-sided

HSK 4 | adverb | mostly true or largely complete

円 (yen, circle): 4 strokes, JLPT N5. On: エン. Kun: まる.

水 (sui/mizu): water. JLPT N5 kanji.

HSK 5 | verb | to cross over or transcend a boundary, gap, or obstacle

HSK 5 | verb/noun | to feel grateful; deep gratitude and appreciation

HSK 5 | adjective | rigorous; meticulous; careful and thorough

HSK 3 | verb | to oppose, to object to, to be against

HSK 4 | adjective | friendly, amicable

HSK 4 | noun | money received from work, business, or investment