1. The tension in the room was at a knife edge as the two rivals faced off.
房间里的紧张气氛如同刀刃一般，两个对手对峙着。

2. The decision hangs on a knife edge, with both options seeming equally risky.
这个决定悬在刀刃上，两个选择看起来同样危险。

3. The team's chances of winning are on a knife edge as they enter the final quarter of the game.
球队赢得比赛的机会在进入比赛的最后一刻时悬在刀刃上。

4. The relationship between the two countries is on a knife edge, with tensions escalating daily.
两国之间的关系如同刀刃一般，紧张局势每天都在升级。

5. The economy is balanced on a knife edge, with any sudden changes likely to tip it into recession.
经济处于刀刃之上的平衡，任何突然的变化都可能使其陷入衰退。

6. His health is on a knife edge, and any further complications could be life-threatening.
他的健康状况如同刀刃一般，任何进一步的并发症都可能危及生命。