be just like
彼は泥棒同然だ。
He's no better than a thief.
彼は赤子同然だ。
He's just like a baby.
彼女は泥棒同然だ。
She's no better than a thief.
ここは我が家同然だぞ
Make yourself at home here.
— レベッカ (1940)
君の言葉は暴力同然だ。
Your words are tantamount to violence.