Acts 1:10

They were looking intently into the sky as He was going, when suddenly two men dressed in white stood beside them.

And while they looked stedfastly toward heaven as he went up, behold, two men stood by them in white apparel;

While they were looking steadfastly into the sky as he went, behold, two men stood by them in white clothing,

Note “Behold”, from “ἰδοὺ”, means look at, take notice, observe, see, or gaze at. It is often used as an interjection.

And while they were looking stedfastly into heaven as he went, behold two men stood by them in white apparel;