"종종, 이러한 노력은 실망과 좌절을 충족." => 종종, 이러한 노력은 실망과 좌절을 충족시킨다 / ... 좌절을 충족한다. (complete sentence) The sentence sounds strange, however, because of 충족시킨다. 충족 (fulfill, satisfy) is usually used in a good sense, like satisfying a need of someone. More natural sounding sentences would be: - 종종, 이러한 노력은 실망과 좌절을 불러 일으킨다 [유발한다 / 가져온다]. (불러 일으키다: give rise to; 유발하다: cause / trigger; 가져오다: bring about) Or - 종종, 이러한 노력은 실망과 좌절을 심화한다 [극대화한다]. (심화하다: further, deepen, worsen; 극대화하다: take to extremes) So, using these words the translation would be: 1. Often, such efforts give rise to [cause / bring about] disappointment and frustration. 2. At times, such efforts worsen[exacerbate] the disappointment and frustration. (#1 for causing it for the first time, #2 if such sentiment already existed)

The sentence isn't complete. The verb is missing.