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thoroughly; through and through; out and out; in every way; from beginning to end; from start to finish
彼は徹頭徹尾、自分の主張を貫いた。
He stuck to his argument through and through.
徹頭徹尾反対の立場を崩さなかった。
They maintained their opposing stance from beginning to end.
この作品は徹頭徹尾、緻密に計算されている。
This work is meticulously calculated through and through.