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

外 (outside): 5 strokes, JLPT N5. On: ガイ、ゲ. Kun: そと、はず-れる.

HSK 5 | verb/noun | to govern or manage; systematic control and management

HSK 4 | verb | shielding someone or something from harm

HSK 5 | noun | supply chain; the network of suppliers, manufacturers, and distributors

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

HSK 5 | noun/adjective | the provision of medical treatment and health services

Learn school vocabulary, how to say where an activity takes place using 在 + place + verb, and common 学习 collocations.

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

HSK 1 | number | the digit four; considered unlucky in Chinese culture due to resemblance to 死 (death)

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

HSK 4 | noun / adjective | mistake; error; wrong; incorrect

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.

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

HSK 1 | noun | things, stuff (idiomatic); east-west (literal)

HSK 4 | noun / verb | going through events that shape understanding

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

HSK 1 | verb | seeing or viewing in multiple senses

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

HSK 9 vocabulary reference: the highest level of the HSK standard, covering literary, classical, and culturally rich Chinese vocabulary.

HSK 4 | noun | quality; standard; mass (physics)

HSK 3 | adjective / adverb | acting on one's own initiative without being asked

We start with a string s. We may delete exactly x characters, keeping the remaining characters in their original order. The resulting string is a subsequence of s. Inside that resulting string, we look for as many non-overlapping occurrences of a pattern p as possible.

HSK 4 | adjective/verb | abstract; to abstract

HSK 5 | adjective | displaying initiative, enthusiasm, or a constructive attitude

Learn how to use 〜に違いない (ni chigainai) to express strong certainty and confident inference — 'must be; there's no doubt that; I'm sure that.' Includes structure, nuance, examples, and comparisons.

Complete katakana chart with all 46 base characters, variants, combination characters, long vowel mark, loanword spelling rules, and common vocabulary examples.

Esperanto vocabulary for time, days of the week, months, seasons, and time expressions.

HSK 4 | noun | an established set of rules or organizational structure

HSK 4 | noun | a person who manages or administers an organization or team

Master six essential Japanese patterns for expressing probability, hearsay, and inference — かもしれない, でしょう/だろう, はずだ/はずがない, らしい, そうだ (two uses!), and ようだ — with a certainty-scale comparison table.

HSK 3 | noun | a physical action or movement of the body

小 (shou/chii-sai): small. JLPT N5 kanji.

HSK 5 | adjective | different from what is normal; exceptional; having unique qualities

HSK 5 | noun | the Internet; the World Wide Web

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

Sindarin vocabulary for warfare, weapons, armor, military ranks, and battle terms — sourced from Tolkien's use of Sindarin in LotR's war contexts.

HSK 4 | noun | boss; owner; employer

Master classical Latin sounds, vowel quantity, diphthongs, and the penultimate accent rule.

HSK 4 | noun | a competitor or rival in business, sports, or other fields

九 (nine): 2 strokes, JLPT N5. On: キュウ、ク. Kun: ここの、ここの-つ.

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

HSK 5 | verb/noun | to assign resources, tasks, or roles according to a plan

Sindarin mixed mutation: the third mutation type triggered by definite prepositions — the complete change table, all triggering constructions, and worked examples.

HSK 3 | noun | a word or short phrase in Chinese

HSK 3 | noun | seafood — fish, shellfish, and other sea creatures eaten as food

Consolidate all B2 grammar and vocabulary, assess your current competency level, identify common B2 errors, and plan your pathway to C1.

HSK 3 | noun / verb | summary, conclusion; to summarize, to wrap up

HSK 3 | noun | a period in history defined by distinctive features

HSK 3 | verb | indicating the origin or source of something

HSK 4 | adjective | diligent, hardworking

We start with a collection of axis-aligned segments. Every segment is either horizontal or vertical, and segments of the same orientation never overlap. We are allowed to delete whole segments or only parts of them.

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

HSK 6 | verb | to deliberately construct or build up a system, framework, or concept

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

HSK 4 | noun | a distinguishing characteristic, feature, or trait

HSK 4 | verb / noun | using existing material as a guide or source

Express additive and cumulative relationships using 不但...而且, 既...又, and 不仅...还 at B1 level.

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

N1 grammar pattern 〜に至って(は): expressing 'now that it has come to ~, upon reaching this extreme point, at this point finally.'

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

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 6 | n | the meaning or significance contained within a word, phrase, or act

HSK 1 | verb | to read text aloud or to study at an institution

Digital transformation, platform economy, and the vocabulary of China's tech-society interface at C1 level

HSK 5 | noun | imagination; the power or capacity to imagine

HSK 4 | adjective | rough, not detailed, approximate

HSK 4 | noun | the outcome or impression produced by an action or cause

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

HSK 4 | noun | a deeply held idea, concept, or way of thinking

We are given an n×n board, where each cell contains either an 'x' or an 'o'. The task is to check a local property for every cell: whether the number of orthogonally adjacent cells containing 'o' is even.

HSK 3 | noun | a goal, target, or objective to aim for

Learn the counter-intuitive grammar of fear clauses and how Latin reports commands indirectly.

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

HSK 5 | verb/adjective | to streamline, trim, reduce to essentials; concise

HSK 2 | noun | a point in time, a moment, an occasion (contrast with 时间)

HSK 3 | verb / noun | to perform, to put on a show; a performance, show

HSK 4 | noun | engineer

HSK 4 | verb | to contact, to come into contact with, to touch

We have a one-dimensional sheet of paper represented as an array of width n. Appleman can fold the sheet at a position p, which means the left segment [0, p) flips and lies over the right segment [p, currentwidth).

HSK 5 | verb/noun | to long for intensely; a strong desire or yearning

HSK 5 | verb/noun | to uplift and motivate someone through an energising or moving influence

HSK 3 | adjective/adverb | paying close attention to detail

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

Master the second declension: masculine -us/-er nouns and neuter -um nouns, with the vocative and neuter rules.

HSK 2 | adverb/adjective | really, truly, genuinely; real, authentic

N1 grammar pattern 〜であれ〜であれ: expressing 'whether ~ or ~' — indicating that the following statement applies regardless of which alternative is the case.

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

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

HSK 3 | preposition | marks passive voice, indicating the subject is acted upon

HSK 3 | noun | the title of a work, the topic of a discussion, or an exam question

HSK 1 | noun/verb | employment, labor; to be employed or carry out a task

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

Develop critical reading skills for Chinese media, mastering the vocabulary and grammar of citation, data interpretation, and source evaluation.

Master the full nuance landscape of purpose and reason in Japanese: 〜ために, 〜ように, 〜から, 〜ので, 〜て (causal), and 〜のに (although/regret). Includes a formality/nuance comparison table and contrasting examples.

HSK 4 | noun / adjective | the system of production and consumption, or economical/thrifty

All four Latin participles (PAP, PPP, FAP, gerundive), their formation and declension, and the ablative absolute construction with worked examples.

HSK 1 | noun | a week; combined with numbers 1–6 or 日/天 to name weekdays

HSK 4 | verb | to cope with; to deal with; to respond

HSK 5 | noun | the ability to produce original and imaginative ideas or works