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that is (to say); namely; i.e.
precisely; exactly; just; nothing but; neither more nor less
(and) then
すなわち、彼は嘘をついたことになる。
That is to say, he lied.
結論、すなわち答えはこれだ。
The conclusion, namely this is the answer.
問題、すなわち根本的な原因を探す。
We seek the problem, namely the cause.