And you shall make: you is singular. Bars of acacia wood uses the word for “crossbars” (Good News Translation) used on doors and gates. Their purpose here was to hold the framework together. They were obviously long horizontal bars, much larger than the poles made for carrying the ark and the table.

Five for the frames of the one side …: this means that the north and south sides of the tabernacle (mishkan) each had five bars, and the side … at the rear westward, that is, the far side at the rear, also had five bars. The same words are used for the far end in verse 22, literally “for the thighs seaward.” (See the comment at verse 22.)

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .