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Learn to describe your daily routine using time adverbs and the -iĝ- suffix for reflexive changes of state.

HSK 5 | verb | to depict; to describe with detail and color

HSK 1 | greeting phrase | expresses sincere apology for a mistake or inconvenience

HSK 4 | noun | the rate at which something moves or happens

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

HSK 5 | noun/adjective | nutrition, nourishment; nutritious

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

青 (sei/shou/ao): blue. JLPT N5 kanji.

HSK 5 | conjunction | let alone; much less; not to mention; all the more so

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

花 (カ/はな): flower; blossom. JLPT N5 essential kanji.

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.

The task revolves around finding two integers, l and r, such that the sum of all digits from l to r modulo a given number a produces an edge case for a buggy implementation. The function f(x) denotes the sum of the decimal digits of x.

HSK 2 | pronoun | reflexive pronoun referring back to the subject

HSK 1 | verb | movement away from the speaker's location

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.

HSK 4 | verb | to guide; to lead; to direct

HSK 4 | noun | the central idea or topic of a work or discussion

Learn to derive nouns, verbs, adjectives, and adverbs from a single root, and to stack multiple affixes for nuanced vocabulary.

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

HSK 3 | verb/noun | to make a request or an appeal

Explore the main uses of the dative (indirect object, possession, reference) and ablative (means, manner, accompaniment, time, prepositions).

HSK 5 | verb/noun | to check and confirm the truth, accuracy, or legitimacy of something

HSK 4 | noun | the specific function or capability of a device, system, or organ

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

Comprehensive guide to HSK 1 grammar: basic sentence structures, question formation, negation, particles, and time expressions with examples.

HSK 4 | verb | indicating the core reason or essence of something

HSK 5 | verb / noun | to argue opposing sides; formal debate

HSK 4 | noun | a list of dishes available at a restaurant

HSK 5 | verb | deliberate increase in scope, scale, or size

Essential Japanese vocabulary for feelings, moods, personality, mental states. N1 level reference with readings, romaji, and examples.

HSK 5 | noun/verb | subjective feeling; to feel or experience something

HSK 2 | verb | to swim; also used as a noun for the sport of swimming

We are given the final state of a system with five participants who started a game under a very rigid rule: everyone begins with the same unknown positive number of coins, call it $b$. After this initialization, coins are only moved between players.

HSK 1 | measure word | classifier for garments and affairs

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

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

HSK 5 | noun/verb | the tendency to align one's behavior with the group

HSK 1 | pronoun | second-person singular pronoun (formal/polite)

HSK 4 | noun | the process or journey through which something develops

HSK 3 | verb | to receive, to collect, to put away

HSK 3 | verb / noun | to criticize, point out faults; criticism

Consolidate B1 grammar patterns and HSK 4-specific vocabulary through integrated review exercises and extended practice.

HSK 2 | verb | to retain something in memory; to recall

HSK 4 | preposition / verb | passing through or using a method

Achieving mastery-level competence in domain-specific Chinese across multiple professional registers.

HSK 3 | verb | to clean up, to sweep — used for cleaning a room or area

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

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

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

HSK 4 | noun | a defined section of space or territory

HSK 3 | adjective | easily seen or understood; unmistakable

HSK 4 | noun | digital platforms for social interaction and content sharing

HSK 3 | verb | to prepare, get ready, or plan to do something

HSK 5 | noun | large-scale digital data sets and their analysis

HSK 2 | noun | a city or urban area

東 (east): 8 strokes, JLPT N5. On: トウ. Kun: ひがし.

HSK 3 | verb / noun | to have a cold; a cold, the common cold

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

Learn how to use 〜さえ〜ば (sae ~ ba) to express the minimum sufficient condition — 'if only ~, then everything is fine.' Includes structure, nuance, examples, and comparisons.

HSK 5 | verb | to present; to display; to bring into view

HSK 1 | proper noun | China

Master the craft of original fiction and poetry in Esperanto, exploiting its unique morphological richness for literary effect.

左 (left): 5 strokes, JLPT N5. On: サ. Kun: ひだり.

HSK 5 | noun | conclusion, final judgement reached through reasoning

HSK 1 | pronoun | third-person singular masculine pronoun

HSK 4 | noun | edible plant parts such as leaves, roots, and stems

HSK 5 | adjective | ahead of the times, at the forefront of development

Learn 〜はおろか to express extreme contrast on a scale — 'let alone X, even Y (which is more basic) is impossible/true.'

HSK 5 | verb / noun | to train; professional training, vocational training

経験 (けいけん / keiken): experience. N4 level Japanese vocabulary.

HSK 3 | verb | to refuse, to reject, to decline

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

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

HSK 4 | adjective | effective or legally valid

HSK 3 | adverb | sets a minimum threshold for quantity, frequency, or degree

Full guide to writing Sindarin in Tengwar: Standard Mode and Mode of Beleriand — with letter tables, vowel placement rules, and practice tips.

HSK 1 | greeting phrase | polite opener before asking a question

HSK 3 | pronoun | each, every, various — refers to all members of a group individually

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 4 | adverb/conjunction | introducing additional information

HSK 3 | verb / noun | to explain, to interpret, to clarify; an explanation

HSK 4 | adjective | referring to a specific, pre-determined thing rather than a general one

HSK 5 | noun | shareholder, stockholder, equity holder in a company

HSK 4 | adverb | describing slow, incremental change over time

HSK 5 | adjective | existing below the surface; not yet apparent; potential

HSK 5 | noun | a concrete example or real-world instance used to illustrate a point

HSK 4 | noun/verb | education; to educate

HSK 5 | noun/verb | to deal with or respond to a difficult situation

HSK 5 | adjective | of great importance, significance, or consequence

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 3 | adverb | on time, punctually, according to schedule

Engage with Chinese discourse on international relations, foreign policy, and globalization, mastering the vocabulary and grammar of global governance.

HSK 5 | noun | systematic body of ideas explaining phenomena

HSK 4 | verb / noun | creating or planning something with purpose and structure

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

HSK 5 | noun phrase | long-term shifts in global or regional climate patterns

HSK 1 | verb | general verb for doing or making something

Constructing and delivering formal argumentation in Chinese debate — 立论, 驳论, and 总结陈词 at C1 level