sternness

例句：

1. 1. She was given a stern look by her boss.
   她被老板严厉地看了一眼。
2. 2. The teacher had a stern tone in his lectures.
   老师讲课时语气很严厉。
3. 3.He was sent to the principal's office for being so stern.
   因为他太严厉了，所以被校长叫到办公室。