Jacob speaks about [Issachar](rc://en/tw/dict/bible/names/issachar) and his descendants as if they are a donkey. This emphasizes that they will work very hard. AT: "The descendants of [Issachar](rc://en/tw/dict/bible/names/issachar) will be like a strong donkey" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Often in prophecy events that will happen in the future are described as something that is already happening. This emphasizes that the event will certainly happen. It can be stated in the future tense. AT: "[Issachar](rc://en/tw/dict/bible/names/issachar) will be" or "The descendants of [Issachar](rc://en/tw/dict/bible/names/issachar) will be"
Possible meanings are 1) "lying down between the packs they were carrying" or 2) "lying down between two sheep pens." Either way, Jacob speaks about [Issachar](rc://en/tw/dict/bible/names/issachar)'s descendants as if they are donkeys that have worked hard and are lying down to rest. (See: [[rc://en/ta/man/translate/figs-metaphor]])