a terribly earnest young man的用法和样例：
- John is a very earnest young man; he should be more cheerful.
- Robert is a very earnest young man ; you can trust him.
- Robert is a very earnest young man; you can trust him.
- The eager and earnest young man already experienced hardship turmoil and the rigors of a full-length day of adult work.
- The salesman was a very personable young man.