Ecclesiastes 2:20 New English Translation

²⁰So I began to despair^[a] about all the fruit of^[b] my labor^[c]
for which I worked so hard^[d] on earth.^[e]

Ecclesiastes 2:20 tn Heb “I turned aside to allow my heart despair.” The term לִבִּי (libbi, “my heart”) is a synecdoche of part (i.e., heart) for the whole (i.e., whole person); see E. W. Bullinger, Figures of Speech, 648.
Ecclesiastes 2:20 tn The phrase “the fruit of” does not appear in the Hebrew text, but is supplied in the translation for clarity (see the following note on the word “labor”).
Ecclesiastes 2:20 tn Heb “all my toil.” As in 2:18-19, the term עֲמָלִי (ʿamali, “my labor”) is a metonymy of cause (i.e., my labor) for effect (i.e., the fruit of my labor). The metonymy is recognized by several translations: “all the fruits of my labor” (NAB); “all the fruit of my labor” (NASB); “all the gains I had made” (NJPS).
Ecclesiastes 2:20 tn Here the author uses an internal cognate accusative construction (accusative noun and verb from the same root) for emphasis: שֶׁעָמַלְתִּי הֶעָמָל (heʿamal sheʿamalti, “the toil for which I had toiled”); see IBHS 167 §10.2.1g.
Ecclesiastes 2:20 tn Heb “under the sun.”

New English Translation (NET)