toss-up
US /ˈtɑːs ʌp/
UK /ˈtɑːs ʌp/

名詞
1.
五分五分, どちらに転ぶかわからない状況, 不確実な結果
a situation in which either of two choices or results is equally possible and it is impossible to predict which will happen
例:
•
It's a toss-up whether she'll get the job or not.
彼女がその仕事を得るかどうかは五分五分だ。
•
The election is a real toss-up between the two main candidates.
選挙は主要な2人の候補者の間で本当に五分五分だ。
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