s unproductive of success
a. 不结果的, 不长果实的, 无子的
1. The search for the missing keys was fruitless.
寻找丢失的钥匙没有结果。
2. After many fruitless attempts, she decided to try a different approach.
经过多次无果的尝试后，她决定换一种方法。
3. His fruitless efforts to convince her only made her more stubborn.
他无果的说服努力只让她变得更加固执。