92 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, .
93 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”).
94 Heb “all my toil.” As in 2:18–19, the term עֲמָלִי (’amali, “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” (); “all the fruit of my labor” (); “all the gains I had made” ().
95 Here the author uses an internal cognate accusative construction (accusative noun and verb from the same root) for emphasis: שֶׁעָמַלְתִּי הֶעָמָל (he’amal she’amalti, “the toil for which I had toiled”); see §10.2.1g.
96 Heb “under the sun.”

In other versions

So I turned about and gave my heart up to despair over all the toil of my labors under the sun,

So my heart began to despair over all my toilsome labor under the sun.

So I began to give myself over to despair concerning all my work that I had labored at under the sun.

So I gave up in despair, questioning the value of all my hard work in this world.

So I began to despair of all the toil with which I toiled under the sun.

Therefore I went about to cause my heart to despair of all the labour which I took under the sun.

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