16 The perfect tense here expresses the experience of a state of mind. As with all who complain in such situations, their memory was selective. It was their bitter cries to the Lord from the suffering in bondage that God heard and answered. And now, shortly after being set free, their memory of Egypt is for things they do not now have. It is also somewhat unlikely that they as slaves had such abundant foods in Egypt.
17 The imperfect tense would here be the customary imperfect, showing continual or incomplete action in past time.
18 The adverb “freely” is from the word חָנַן (khanan, “to be gracious”), from which is derived the noun “grace.” The word underscores the idea of “free, without cost, for no reason, gratis.” Here the simple sense is “freely,” without any cost. But there may be more significance in the choice of the words in this passage, showing the ingratitude of the Israelites to God for His deliverance from bondage. To them now the bondage is preferable to the salvation—this is what angered the Lord.

In other versions

We remember the fish we ate in Egypt that cost nothing, the cucumbers, the melons, the leeks, the onions, and the garlic.

We remember the fish we ate in Egypt at no cost—also the cucumbers, melons, leeks, onions and garlic.

We remember the free fish we ate in Egypt, along with the cucumbers, melons, leeks, onions, and garlic.

“We remember the fish we used to eat for free in Egypt. And we had all the cucumbers, melons, leeks, onions, and garlic we wanted.

We remember the fish that we ate in Egypt for nothing, the cucumber, melon, leek, the onions, and the garlic.

We remember the fish, which we did eat in Egypt freely; the cucumbers, and the melons, and the leeks, and the onions, and the garlick:

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