Topic は, question か, and the negative
Japanese sentences are built around two tiny particles you'll meet in nearly every sentence: は marks the topic ('as for X...') and か turns a statement into a question. Once you can drop them in, you can ask and answer the basic 'who is X?' questions on day one.
Pronouns — and dropping them
わたし = I (polite, gender-neutral). あなた = you — but careful: Japanese speakers usually use the person's name + さん instead, because あなた can sound blunt or even like a wife addressing her husband. かれ = he / boyfriend. かのじょ = she / girlfriend. The big rule: when the listener already knows who you mean, drop the pronoun. がくせい です。 by itself can mean 'I'm a student' or 'he's a student' depending on context — and that's fine.
は — the topic particle
は (written as the kana は but pronounced 'wa' when used as a particle) marks what the sentence is about. Pattern: [topic] は [comment]. わたし は がくせい です。 = 'as for me, (I'm) a student'. やまだ さん は せんせい です。 = 'as for Yamada, (he/she's) a teacher'. The topic isn't always the grammatical subject — but for now, it usually is.
か — turning a statement into a question
Add か at the very end of a sentence and your statement becomes a yes/no question. No rising intonation, no inverted word order needed. がくせい です。 (you're a student.) → がくせい です か。 (are you a student?). Japanese question marks aren't required when か is there — a regular period is fine. To answer: はい、がくせい です。 or いいえ、がくせい じゃ ありません。
Negation — じゃ ありません
To say 'is not', replace です with じゃ ありません (or the more formal では ありません). わたし は せんせい じゃ ありません。 = 'I'm not a teacher'. The casual contraction じゃ ('ja') comes from では — both are correct, じゃ ありません is what you'll hear in everyday polite speech.
Naming people: ~さん
Add さん after someone's name as a polite default — like 'Mr./Ms.' but used much more broadly. やまだ さん, アナ さん. Never add さん to your own name. For teachers and doctors use せんせい instead of さん: やまだ せんせい.
