To sit on the fence 中立/观望不表态
Frankel, a prize-winning race horse who was retired in 2012, ran 100 metres in 5.2 seconds. That compares to runner Usain Bolt, who ran 100m in 9.63 seconds, and cyclist Jason Kenny, who has raced the same distance in 4.86 seconds.
这个短语 to sit on the fence 的意思就是采取中立态度，坐山观望不表态。
I'm sitting on the fence. I don't know who is right or wrong.
I prefer to sit on the fence. I hate taking sides in any argument.
He's so indecisive. He always prefers to sit on the fence.
另一个短语 to sit tight 意思是静静地观望形势，再决定下一步怎么走。
You're best to sit tight. It's too risky to change jobs now.