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HSK 3 | verb | to love something with great passion

HSK 5 | noun/adjective | the decisive or most critical element

Learn to describe where things are using 在 and position words like 上面, 里面, and 前面.

HSK 5 | adjective / adverb | basic, fundamental, essential; basically, fundamentally

HSK 8 | noun | fluid dynamics; the study of forces and motion in liquids and gases

We are given a set of n distinct integers. Every number must be assigned to one of two groups. If a number x is placed into group A, then its complement with respect to a, namely a - x, must also be present and must belong to A.

Master the accusative + infinitive construction (ACI) used after verbs of saying, thinking, and perceiving.

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

HSK 3 | verb | to give as a gift, deliver, or accompany someone when they leave

高 (high, expensive): 10 strokes, JLPT N5. On: コウ. Kun: たか-い、たか.

HSK 5 | adjective | superb, consummate, highly skilled

The problem presents a simple scenario: George and Alex want to find a dormitory room together. Each room in the dormitory has a current occupancy and a maximum capacity.

Master Chinese rhetorical devices including parallel structure and rhetorical questions, and develop the ability to write and recognize persuasive Chinese prose.

HSK 4 | noun | lawyer; attorney

HSK 5 | noun | a branch of academic study or knowledge

HSK 5 | verb | to explore; to examine through discussion or inquiry

Describe your home, talk about where you live, and discuss renting and moving in Chinese.

HSK 2 | adjective/verb | to be anxious, worried, or in a rush

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

The task is to construct n sets of four distinct positive integers, where each set has a certain "rank" k. The rank condition requires that the greatest common divisor (GCD) of any two numbers within the set equals exactly k.

HSK 4 | conjunction | introduces a concessive clause

HSK 5 | noun | an organized collection of structured data stored and accessed electronically

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

HSK 5 | adjective | reasonable, rational, sensible, justified

HSK 4 | noun/verb | an official notice or the act of informing someone

HSK 5 | noun | one's sense of self and identification with a group or role

Learn body parts, health vocabulary, and how to describe symptoms and visit a doctor in Esperanto.

HSK 5 | verb/noun | the act of holding someone responsible for their actions or failures

HSK 5 | verb/noun | natural or observable change in state or condition

六 (six): 4 strokes, JLPT N5. On: ロク. Kun: む、む-つ、むっ-つ、むい.

HSK 5 | noun | a physical, mathematical, or conceptual representation of a system or object

HSK 3 | noun | any audible sound or a person's voice

HSK 2 | noun / localizer | the side of something; used to indicate adjacency

HSK 4 | verb | bearing responsibility for a task or outcome

The complete sound change history from Primitive Elvish through Common Telerin and Old Sindarin to Classical Sindarin — explaining WHY mutations exist and how the vowel system developed.

HSK 4 | verb / noun | making or experiencing a shift in condition or nature

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

HSK 5 | noun/adjective | the relationship between living organisms and their environment

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

HSK 3 | conjunction | moreover, and also, furthermore — adds an additional point

HSK 3 | verb | to carry out, conduct, or be in progress

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

HSK 3 | adjective | young in age or youthful

HSK 6 | verb | to promote and carry forward something of cultural or moral value

We have an $n times n$ chessboard, and each cell has a non-negative integer representing money. The goal is to place exactly two bishops such that no cell is attacked by both bishops, and we maximize the total money collected from all cells that are attacked by at least one…

HSK 5 | noun / verb | reform, transformation, fundamental change

Master all four tenses of the Latin subjunctive and learn to form purpose clauses with ut and ne.

HSK 3 | noun | the center or core of something

HSK 5 | verb / noun | to clarify or illustrate; an explanation or instructions

Sindarin possessive pronouns: suffix forms attached to nouns, independent possessive forms, and the genitive construction with en.

N1 grammar pattern 〜ともあろう: expressing indignation or disbelief that someone of high standing has done something unworthy of their position.

Explore all major uses of the accusative and genitive cases, including prepositions, partitive genitive, and genitive of description.

HSK 3 | noun | a distinguishing quality or trait

HSK 4 | verb | to make smaller or narrower

駅 (eki/): station (train/bus). JLPT N5 kanji.

We need to print an odd-sized square grid that contains a diamond shape. Every cell belonging to the diamond is represented by the character D, and every other cell is represented by . The input contains a single odd integer n.

HSK 3 | noun | a positive quality or strength of a person or thing

Learn how to use 〜てならない (te naranai) to express feelings or states that arise spontaneously and overwhelmingly — 'can't help but feel ~.' Includes structure, nuance, examples, and comparisons.

百 (hyaku/momo): hundred. JLPT N5 kanji.

HSK 3 | verb / noun | to notify, inform, announce; a notice or announcement

HSK 5 | noun | energy, energy resources, power supply

Complete guide to all 5 Sindarin consonant mutations: soft (lenition), nasal, mixed, stop, and liquid — with full tables, triggers, and worked examples.

HSK 5 | noun | the state of balancing carbon emissions with carbon removal

HSK 5 | noun | the arrangement of people or things according to rules and structure

Express comparisons of superiority, inferiority, equality, and progressive change using pli, malplej, same kiel, and related structures.

赤 (seki/shaku/aka): red. JLPT N5 kanji.

〜せる/〜させる: JLPT N4 grammar pattern. Usage, structure, examples, and comparison with similar patterns.

10 structured lessons for JLPT N4: from reviewing N5 basics to complex grammar, passive/causative, conditionals, and practical reading/writing. Each lesson includes dialogues and exercises.

HSK 1 | noun | man, male adult

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

HSK 5 | verb/noun | growth and advancement toward a more complete state

校 (kou/): school. JLPT N5 kanji.

店 (store, shop): 8 strokes, JLPT N5. On: テン. Kun: みせ.

HSK 4 | noun | the nutrients and nourishment that the body needs

HSK 2 | adjective | a feeling of happiness and joy

HSK 3 | verb/noun | to eagerly anticipate something

HSK 3 | noun | attitude, manner, approach — how someone behaves or feels toward something

HSK 5 | noun/adjective | network; the internet; online

HSK 5 | noun | economic activity driven by digital technologies and data

Sindarin words for people, races, relationships, titles, and names for individuals.

HSK 3 | adverb | happening infrequently or from time to time

HSK 5 | verb/noun | official supervision and control by a regulatory authority

一 (one): 1 strokes, JLPT N5. On: イチ、イツ. Kun: ひと、ひと-つ.

Essential Japanese vocabulary for stores, prices, shopping, money, bargaining. N1 level reference with readings, romaji, and examples.

HSK 5 | adjective | delicately complex in a way that is difficult to analyze or describe

HSK 3 | noun | the purpose or range of uses that something has

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

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

Sindarin i-affection plural formation: the a→ai, e→i, o→y vowel change patterns with 30+ worked examples.

HSK 1 | greeting phrase | affirms agreement or acknowledges a request

HSK 4 | verb | to communicate or signal a feeling, attitude, or meaning

HSK 1 | noun | a male child

HSK 1 | pronoun | third-person plural pronoun (masculine or mixed)

HSK 1 | noun | table, desk

HSK 5 | noun | factual evidence used to establish the truth of something

先 (before, ahead): 6 strokes, JLPT N5. On: セン. Kun: さき.

市 (city, market): 5 strokes, JLPT N5. On: シ. Kun: いち.

Master formal request forms, business vocabulary, and the foundations of keigo (honorific language) for N3-level workplace communication: emails, phone calls, meetings, and the 丁寧語/尊敬語/謙譲語 distinction.

HSK 4 | noun | experience gained through practice or life

Essential Sindarin greetings and phrases directly from Tolkien's texts: Mae govannen, Hannon le, Navaer, Le abdollen, and more.