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HSK 2 | adjective | describes an absence of noise or disturbance

HSK 5 | adjective | appropriate; suitable; fitting for the context

Six graded Sindarin reading passages from beginner to advanced: all fully glossed with word-by-word translation, grammatical notes, and cultural commentary.

HSK 3 | adjective | simple, easy, uncomplicated, plain

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

HSK 3 | grammar pattern | softens a comparative or evaluative statement with 'a bit'

Master Esperanto's 28-letter phonemic alphabet, including the six diacritic letters and the X-system alternative.

HSK 4 | noun | situation; circumstances; condition

HSK 3 | noun | a written character, word, or one's handwriting

HSK 3 | conjunction | as long as, provided that — states the minimum condition for a result

We are given a fixed amount of money expressed in dollars, and a list of sugar options in a supermarket. Each option has a price written as dollars and cents.

Learn how to use 〜てたまらない (te tamaranai) to express unbearable or overwhelming feelings, sensations, or desires — 'can't stand ~; unbearably ~.' Includes structure, nuance, examples, and comparisons.

HSK 4 | verb | to reflect a situation or to report a problem to a higher authority

We are given a binary string that represents a positive integer $x$. Instead of directly printing this binary number, we are forced into a strange process that maintains a single integer variable $n$, starting at zero, and builds the output by repeatedly applying only two…

HSK 5 | noun | surgical operation; medical procedure involving cutting

半 (han/naka-ba): half. JLPT N5 kanji.

Learn how to use 〜ばかりか (bakari ka) to express 'not only ~ but even ~' with an emphasis on escalating or surprising addition. Includes structure, nuance, examples, and comparisons.

HSK 5 | conjunction | as a result; causing; so that (introducing a negative consequence)

HSK 4 | verb | to hold an opinion or belief about something

Learn how to express passive constructions in Chinese using 被, 让, and 叫, and understand when passive voice is appropriate in Mandarin.

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

HSK 3 | noun | weekend, Saturday and Sunday

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

HSK 1 | noun | student, pupil

All Sindarin dictionaries compared — Parf Edhellen, Eldamo, Hiswelókë — with guidance on when to use each and how to interpret source period labels.

HSK 4 | verb | experiencing sudden surprise or shock

HSK 5 | verb | to examine and check something carefully for accuracy or compliance

HSK 5 | verb/adjective | to make something more complete or perfect; fully developed

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

HSK 5 | verb/noun | to limit or restrict the scope of action; a constraint or limitation

HSK 4 | adjective / verb | noticeably prominent or to protrude beyond others

HSK 5 | verb/noun | to assess, evaluate, or appraise performance; an assessment

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

Learn 〜からすると, 〜からすれば, and 〜からみると to express judgments and inferences from a specific perspective or standpoint.

Order food, ask questions, and handle the bill in Chinese with practical restaurant vocabulary and grammar.

HSK 4 | verb / noun | to formally apply for something; an application

HSK 5 | verb/noun | the state of being unable to repay debts; financial insolvency

Japanese nature vocabulary: weather, animals, plants, landscape, environment, and natural phenomena.

HSK 5 | verb | to become involved in a situation in order to influence its outcome

HSK 4 | noun | a raised surface or an opportunity base for activity

HSK 4 | noun | client, customer

HSK 3 | grammar pattern | additive correlative conjunction expressing escalation

HSK 5 | noun | a firmly held belief or conviction that guides one's actions

HSK 2 | noun | father's mother (paternal grandmother)

HSK 3 | adverb | mutually, each other — describes an action done by both parties toward each other

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

HSK 3 | conjunction | adds an additional point to what was already stated

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

Victor wants to build a set of integers within a specified range such that the XOR of all its elements is minimized. The set can contain up to k elements, all distinct, and every element must lie between l and r inclusive.

Learn how to use 〜に加えて (ni kuwaete) to express 'in addition to' when adding further information or elements. Includes structure, nuance, examples, and comparisons.

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

HSK 4 | noun | a person who shares in a business venture or partnership

HSK 5 | noun | ozone layer, the stratospheric layer that absorbs ultraviolet radiation

HSK 5 | noun / verb | the point from which something originates; to originate from

HSK 4 | noun | an organizational unit within a larger body

Form yes/no questions with ĉu, use wh-questions fluently, and express, agree with, and politely challenge opinions.

HSK 5 | noun | administrative regulations and legal rules issued by authorities

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

Discuss economic and business topics using 在...方面, 就...而言, and formal business vocabulary at B1 level.

HSK 3 | noun | method, way, approach — a systematic means of doing something

HSK 3 | noun | the meaning of a word or the idea behind something

HSK 3 | noun | an indoor facility for sports and physical activities

Learn how to use 〜に先立って (ni sakidatte) to express 'prior to' or 'before' when an action precedes an important event. Includes structure, nuance, examples, and comparisons.

Learn how to use 〜をはじめ (wo hajime) to express 'starting with' or 'including' when listing a representative example of a broader group. Includes structure, nuance, examples, and comparisons.

HSK 3 | verb / adjective | to be moved emotionally, touched deeply by something

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

子 (shi/su/ko): child. JLPT N5 kanji.

Learn the formal conjunctive particle 〜において (in, at — domain marker) and its attributive form 〜における, essential for N3 reading and formal written Japanese.

HSK 5 | noun | the financial gain remaining after subtracting all costs from revenue

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

Learn everyday Japanese verbs, understand u-verb and ru-verb conjugation, and express present, past, and negative actions using the polite ます form.

Learn 〜ものがある (there is something ~ about it, it has a certain quality) — the N3 pattern for expressing an indefinable or deeply felt quality.

HSK 4 | noun / verb | plan; to plan; to intend

HSK 1 | phrase | negates identity or equation using the verb 是

We have an $n times n$ bingo board. Every cell contains a distinct number chosen from $1$ to $m$, and every valid board is equally likely. After the board is generated, exactly $k$ distinct numbers are called. Every set of $k$ numbers is equally likely.

HSK 1 | noun | mobile phone, smartphone

HSK 3 | verb | to come into view or to happen for the first time

HSK 4 | noun/verb | professor; to teach, to instruct

新 (new): 13 strokes, JLPT N5. On: シン. Kun: あたら-しい、あら-た、にい.

HSK 5 | discourse marker | in other words; to put it another way

Learn how Latin adjectives agree with nouns in gender, case, and number using the bonus/bona/bonum model.

HSK 4 | verb / noun | rallying people to a cause or action

HSK 6 | verb | to bring together disparate elements into a unified whole

HSK 4 | verb | disrupting someone's activity or peace

HSK 4 | adjective | fully adequate in amount or degree

HSK 5 | verb | to convey; to relay; to pass on (information, instructions, or feelings)

HSK 3 | verb | to convey thoughts or feelings

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

HSK 4 | adjective | showing energy, initiative, and a constructive attitude

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

Consolidate all A1+ grammar patterns and the most important HSK 2 vocabulary through integrated exercises and review.

HSK 5 | noun | performance; capability; functional properties of a product or system

HSK 1 | pronoun | first-person singular pronoun

HSK 3 | adverb / adjective | certainty or a fixed amount

HSK 3 | modal verb | must, have to — expresses strong obligation or necessity

HSK 2 | adjective | easy to do, likely to happen

HSK 4 | verb/noun | to strive against others for the same goal or resource

Learn to describe your daily routine using V + 了 for completed actions and sequence time words.

HSK 3 | adjective | fierce, severe, formidable, impressive — colloquial praise or warning

HSK 5 | verb / noun | to demonstrate the truth of something; a document proving a fact