虚拟语气的if从句可以省略if，但须把助动词提前至从句的句首，所以本句中were在句首。
再如：
- How terrible it would have been had we missed the chance! 如果我们当时错过了那次机会，情况会多么糟糕啊！（2020高考天津卷阅读D篇）
此句省略了if，所以提前了助动词had，完整形式为：…if we had missed the chance。
练一下：
In fact, he would be charged ____ (be) he alive.
答案：were；本句为虚拟语气，省略了if，其完整表达形式是：In fact, he would be charged if he were alive. 句意为：事实上，如果他活着，他将受到指控。
