Japanese 「AはBです」 is one of the most fundamental sentence patterns in Japanese. This guide explains its topic-and-explanation structure, common uses for identity, places, time, and contrast, and how it differs from 「AがBです」.

「〜次第だ」 does more than vaguely mean “it depends.” It identifies the condition that determines an outcome. This guide explains noun＋次第だ, 次第で, and 次第では through examples involving effort, weather, conditions, and responses, compares them with 〜による and Korean equivalents, and distinguishes separate uses such as 分かり次第.

Japanese 「〜し」 can list multiple reasons, present one reason while implying others, and leave a conclusion unstated at the end of a sentence. This guide covers its attachment patterns, major uses, comparisons with 「〜から／〜て」, conversational usage, and related Korean forms.

「〜たつもり」 expresses a subjective belief that an action has already been completed, even when reality may be different. This guide compares it with related 「つもり」 patterns and explains its use in understanding, hypothetical mindsets, and business situations.

Japanese academic writing involves more than changing 「です・ます」 to 「である」. It requires clear scope, evidence, and inferential relationships. This guide explains 「である調」, objective inference, formal connectors, and common structures used in Japanese university reports and research abstracts.

〜つもり emphasizes personal intention, decisions, and intent, while 〜予定 focuses on established plans and schedules. The article also covers negative forms, extended uses of つもり, common errors, practical dialogues, and a comparison with Korean -(으)ㄹ 생각이다／예정이다.

The key to 「〜ていく／〜てくる」 is not a simple “go vs. come” translation, but the direction of movement after an action relative to a reference point. This guide compares 「買っていく／買ってくる」 and 「持っていく／持ってくる」 with practical examples.

Japanese frequently omits subjects without making meaning unclear. This article explains how to identify omitted subjects through prior topics, shared context, conversational situations, 「は／が」, honorifics, and giving-and-receiving expressions, while also comparing 「私は」, 「あなた」, and Korean subject omission.

〜始める, 〜出す, 〜続ける, and 〜終わる attach to the Japanese ます-form stem and show different stages of an action. 〜始める marks a neutral beginning, 〜出す often highlights a sudden start, 〜続ける shows continuation, and 〜終わる marks completion. The article compares them through examples, timelines, and Korean equivalents.

Japanese often manages interpersonal distance through tentative language, conditional requests, softening phrases, and indirect refusals. This article explains how 「かもしれません」, 「よろしければ」, and 「少し難しいです」 function in workplace, travel, and invitation contexts.

「〜かもしれない」 expresses a more reserved possibility, while 「でしょう」 often signals a more evidence-based judgment or soft confirmation. This guide compares both through examples, travel conversations, and Korean equivalents.

「〜はずだ」 expresses a confident inference based on evidence, while 「〜はずだった」 shifts that expectation into the past and often suggests a mismatch with reality. This guide covers attachment rules, present and future inference, failed expectations, travel dialogues, and a Korean comparison.