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HSK 2 | particle | expressive sentence-final particle with four tonal variants

明 (mei/myou/aka-rui): bright. JLPT N5 kanji.

We are given an undirected graph and, for every vertex, the parity of how many times that vertex must appear in a walk. A walk is represented by a sequence of vertices. Consecutive vertices in the sequence must be connected by an edge.

火 (ka/hi): fire. JLPT N5 kanji.

Top 10 mistakes English speakers make in Esperanto — grammar errors, pronunciation issues, and common misconceptions.

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 1 | noun | one's younger brother

HSK 4 | noun | friend; companion

HSK 3 | adjective | deep (physical), dark (color), or profound (abstract)

HSK 4 | noun | money available for investment or use in a project

Learn how to use 〜に際して (ni saishite) to express 'on the occasion of' or 'at the time of' for significant events and actions. Includes structure, nuance, examples, and comparisons.

HSK 3 | adjective | cute, adorable, or lovely

〜てみる: JLPT N4 grammar pattern. Usage, structure, examples, and comparison with similar patterns.

We are given several piles of worms arranged in order. The worms are numbered consecutively across all piles. If the pile sizes are: then the first pile contains worms numbered 1 through 2, the second pile contains worms numbered 3 through 9, and the third pile contains worms…

HSK 4 | adjective | having all necessary parts and nothing missing or damaged

HSK 5 | conjunction | even if, even though, no matter (strong concession)

Learn 〜として (as, in the capacity of) — the N3 pattern for expressing roles, identities, functions, and premises.

N1 grammar pattern 〜にほかならない: emphatic definitional assertion — X is nothing other than Y. Used for declarative identification, formal analysis, and rhetorical emphasis.

HSK 5 | verb | to make something firmer, stronger, or more secure

HSK 5 | noun | background, backdrop, context, personal connections

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

HSK 3 | verb | to finish, accomplish, or fulfill a task or goal

HSK 3 | adjective/adverb | arriving or happening at the scheduled time

HSK 3 | adverb | refers to a subset within a previously mentioned group or set

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

HSK 3 | noun | the monetary value of a product or service

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

HSK 5 | noun | financial returns or gains from an activity or investment

HSK 4 | conjunction | expressing unconditional situations

N1 grammar pattern 〜かたわら: expressing that someone pursues a secondary activity alongside a primary one — while also, on the side.

HSK 3 | adverb | restrictive adverb expressing lateness, difficulty, or limited scope

Japanese food and drink vocabulary: common foods, drinks, cooking methods, restaurant expressions, and traditional Japanese cuisine terms.

HSK 5 | noun | arrangement and organization of components within a whole

HSK 5 | verb | to recruit; to enlist members, volunteers, or employees

〜が (ga): JLPT N5 grammar pattern. Usage, structure, examples, and comparison with は.

HSK 5 | noun | innate ability or formal qualification for a role

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

HSK 3 | verb | to hurry toward something or catch a vehicle in time

HSK 5 | verb/adjective | to contain something hidden within; not explicitly stated

HSK 4 | adverb / noun | referring to a specific past moment

Complete JLPT N5 exam prep: format breakdown, 20 vocabulary practice questions, 20 grammar practice questions, 2 reading passages, listening strategies, 30-day study plan, mnemonics, and common traps.

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 | verb | to form; to come into being; to develop into

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 4 | noun | distinguishing feature or characteristic

Apply all intermediate constructions to Caesar's De Bello Gallico, with a full analysis of BG 1.1.

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

HSK 3 | noun | passport — official travel document

HSK 5 | noun | observable direction of development or change over time

だから (だから / dakara): therefore, so. N4 level Japanese vocabulary.

HSK 4 | n/adj | a system of government by the people; fair and open

HSK 1 | measure word | general classifier for people and objects

HSK 3 | noun | neck, the part of the body connecting the head to the shoulders

HSK 3 | verb | to lose a game, match, or contest

HSK 3 | noun / adjective | major field of study; specialized skill or knowledge

Essential Japanese vocabulary for illness, medicine, hospitals, exercise, nutrition. N1 level reference with readings, romaji, and examples.

HSK 3 | verb + directional complement | to carry something out of an enclosed space, away from the speaker

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

HSK 4 | n | money collected by the government through taxes

HSK 1 | pronoun | interrogative pronoun asking about a person's identity

We are given an undirected weighted graph representing cities and roads. City 1 is the capital. In addition to normal roads, there are special train routes that connect the capital directly to some city. The government wants to close as many train routes as possible.

We are asked to compute the permanent of a large square matrix where almost every element is 1, and only a small number of entries are different.

HSK 3 | noun | an official public holiday or a day free from work

HSK 1 | adjective | tall, high, of great height

HSK 3 | adjective | feeling emotional pain or sadness

HSK 3 | noun / verb | development, growth; to develop, to expand

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

Mastering 之、乎、者、也 and the grammar of classical Chinese in modern scholarly and literary contexts.

HSK 3 | verb + result complement | to express something in a way that is fully understood

HSK 5 | noun | a public forum for discussion; an online discussion board

はっきり (はっきり / hakkiri): clearly. N4 level Japanese vocabulary.

HSK 1 | noun | friend

HSK 1 | verb, preposition | to use, to employ, with (using)

HSK 5 | noun | ability, capability, capacity to do something

HSK 3 | adjective / adverb | special, particular; especially, particularly

HSK 4 | noun | doctor, physician

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.

Appleman starts with an empty string. In one second he may append any substring of t to the end of the string he is building. For a fixed target string s, Appleman chooses an optimal sequence of substrings and finishes s in the minimum possible number of seconds.

HSK 5 | adjective/adverb | expressing the idea of being contrary or the reverse

Express a full range of emotions in Esperanto, describe how you feel, use -iĝ- for emotional changes, and comfort others in conversation.

HSK 5 | noun/adjective | freedom, liberty; free, unrestricted

Learn 〜ことなしに (without doing ~) — the formal N3 pattern expressing that one action is performed without the prerequisite action.

N1 grammar pattern 〜べく: a formal literary purposive expressing 'in order to ~, for the purpose of ~' — the written formal equivalent of ために.

HSK 5 | verb | to breed, to nurture, to cultivate (plants, organisms, or people)

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

HSK 4 | conjunction | although; even though; though

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

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

雨 (u/ame): rain. JLPT N5 kanji.

HSK 2 | noun | a sovereign state or nation

それから (それから / sorekara): and then, after that. N4 level Japanese vocabulary.

The document can be viewed as a vertical stack of rows, where each row has a fixed length and the cursor always sits at some coordinate inside this grid.

Learn 〜をはじめとして and 〜をはじめとする to introduce a representative example from a larger group in formal Japanese.

HSK 4 | noun | experience gained through practice or life

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

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

10 structured lessons building JLPT N5 from zero: hiragana/katakana mastery, self-introduction, numbers, places, daily activities, shopping, adjectives, past tense, desires, and plans.

HSK 3 | verb | to successfully obtain, receive, or achieve something

HSK 3 | verb | to continue or keep doing something

先 (sen/saki): before. JLPT N5 kanji.