Kugi wo Sasu (釘を刺す Warning against Someone)

To give someone a warning in advance in order not to cause a problem later is referred to as 釘を刺す (kugi wo sasu) in Japanese.

釘 (kugi) means "nail" and 刺す (sasu) means "to drive," so the literal meaning of "kugi wo sasu" is "to drive a nail (into someone)."

This expression comes from the construction method in Japan.

In the past, Japanese people built buildings only by assembling timbers, but later we have come to drive nails to fix them for the sake of safety.

Because of this, "kugi wo sasu" has come to mean to warn against someone for safety purposes.

釘を刺す

人に対して、あとで問題が起きないように念を押すことを、「釘を刺す」と言います。

「釘」は "nail," 「刺す」は "to drive" を意味するので、「釘を刺す」の文字どおりの意味は "to drive a nail (into someone)" となります。

この表現は、日本における建築の工法に由来します。

かつて日本では、釘を使わずに木材を組み込んで建築を行っていましたが、後に念のために釘を打って固定するようになりました。

このことから、人に対して前もって念を押すことも、「釘を刺す」と言うようになりました。

• This expression comes from the construction method in Japan.
• This expression comes from the construction method in Japan.

• In the past, Japanese people built buildings only by assembling timbers, but later we have come to drive nails to fix them for the sake of safety.
• In the past, Japanese people built buildings only by assembling timbers, but later we have come to drive in nails to fix them for the sake of safety.

  This would be slightly better I think, to distinguish this "drive" from 運転する.

What great English! The only problem I found was that the style is a little stiff or formal.