He saw is in Greek a form of the present tense for the sake of vividness (see v. 27).

The word translated something is the same word that was used in 9.15 (literally “vessel” or “instrument”), and is used here in the most general sense possible, meaning simply a “thing.” A similar use of this word is found in Mark 11.16.

The passive expression being lowered by its four corners may cause certain difficulties in languages which cannot employ such a passive construction. Obviously, in this context there is no indication of the agents, but one can render such a passive expression as “it came down as though someone were holding it by its four corners” or “it came down as though people were holding it by the four corners.” (In such an expression, however, it is necessary to make certain that one does not specifically imply that people were actually doing this. It was only “as though they were doing it.”)

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on The Acts of the Apostles. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .