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generally; on the whole; mostly; almost; nearly; approximately; roughly; about
general; rough
outline; main points; gist; substance; essence
in the first place; first and foremost; from the start; to begin with
大体の内容はわかりましたか。
Did you mostly understand?
大体の予定はもう決まった。
The general schedule was decided.
大体三十分くらいかかる。
It takes about thirty minutes.