swords
A sword is a weapon with a handle and a long sharp blade.
cross swords
If you cross swords with someone, you disagree with them and argue with them about something.
a candidate who's crossed swords with Labour by supporting the free-trade pact.
一位因支持自由贸易协定而与工党争论的候选人。
a double-edged sword
If you say that something is a double-edged sword, you mean that it has negative effects as well as positive effects.
A person's looks are a double-edged sword. Sometimes it works in your favour, sometimes it works against you.
人的相貌是一把双刃剑,有时它对你有利,有时又对你不利。