例句：
1、It would be a mistake to understate the seriousness of the problem.
对该问题的严重性轻描淡写是错误的。
2、The seriousness of the situation is difficult to appreciate in its totality.
很难从全局上理解局势的严重性。
3、He hasn't yet woken up to the seriousness of the situation.
他还没有认识到形势的严重性。
4、He spoke with a seriousness that was unusual in him.
他说话时神情少有地认真。