Exodus 27:8

27:8 You are to make the altar hollow, out of boards. Just as it was shown you ¹  on the mountain, so they must make it. ² 

Exodus 38:7

38:7 He put the poles into the rings on the sides of the altar, with which to carry it. He made the altar ³  hollow, out of boards.

[27:8]  ¹ tn The verb is used impersonally; it reads “just as he showed you.” This form then can be made a passive in the translation.

[27:8]  ² tn Heb “thus they will make.” Here too it could be given a passive translation since the subject is not expressed. But “they” would normally refer to the people who will be making this and so can be retained in the translation.

[38:7]  ³ tn Heb “it”; the referent (the altar) has been specified in the translation for clarity.