particle omission
か as question marker becomes rising intonation.
は、が、を、へ（に）if meaning clear from context.
に、で、から、まで、と not omitted as needed for meaning.
contraction
〜ている becomes 〜てる
〜ちない becomes 〜てない
だ omission
In questions and answers with noun and なadjectives. だ is often omitted.
だ in an answer can sound harsh (also masculine). can be softened to だよ (or just よ for female speech)
けど
same function as が meaning but.
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