Learn Hardcore Indonesian: Kami mencatat nomor kursi sebelum acara dimulai. - We record the seat numbers before the event starts.

Kami means “we” but excludes the listener; kita includes the listener. The sentence suggests the listener wasn’t part of the group doing the action. If you want to include the listener, say: Kita mencatat nomor kursi sebelum acara dimulai.

There’s no past tense marking. How do I show past or future?

Indonesian doesn’t inflect verbs for tense; time is shown with time words:

Past: sudah, tadi, barusan (e.g., Tadi kami mencatat nomor kursi…).
Future: akan, nanti (e.g., Kami akan mencatat nomor kursi…). Here, sebelum already anchors the time sequence (“before”).

What’s the nuance of mencatat compared with menulis?

Mencatat = to note down, record for reference (e.g., minutes, data, numbers).
Menulis = to write (general writing). For seat numbers, mencatat nomor kursi is natural. Other options: merekam (to record audio/video), menandai (to mark/highlight).

Why nomor, not angka or jumlah?

Nomor = an identifying number (seat number, phone number). So is correct.