rub
US /rʌb/
UK /rʌb/

動詞
1.
名詞
1.
2.
問題, 困難
a difficulty or problem, especially one that is hidden or not immediately obvious
例:
•
The only rub is that we don't have enough money.
唯一の問題は、私たちには十分なお金がないことです。
•
Here's the rub: we need to finish this by tomorrow.
ここが問題だ:明日までにこれを終える必要がある。
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