先(ま)ず以(もっ)てfirst of all, in the first place

体調(たいちょう)が悪(わる)い時(とき)は先(ま)ず以(もっ)て休(やす)むべきだ。

When you're feeling unwell, you should, first of all, take a rest. {first of all, in the first place}

仕事(しごと)終(お)わりにまずもってビールを飲(の)みました。

First of all, I drank a beer after finishing work. {first of all, in the first place}

父(ちち)が娘(むすめ)に：「妊娠(にんしん)したのか？まずもってめでたいことだ！」

The father said to his daughter: "Are you pregnant? First of all, that's wonderful news!" {first of all, in the first place}

母(はは)が娘(むすめ)に：「言(い)い訳(わけ)をする前(まえ)に、まずもって弟(おとうと)に謝(あやま)りなさい！」

The mother said to her daughter, "Before making excuses, first of all, apologize to your younger brother!" {first of all, in the first place}

医師(いし)：「心肺(しんぱい)蘇生(そせい)が成功(せいこう)しました。親御(おやご)さん、これで先(ま)ず以(もっ)て安心(あんしん)です。」

Doctor: "The cardiopulmonary resuscitation was successful. Parents, you can be assured for now." {first of all, in the first place}