"This place is a xenomorph infestation site. Everybody is either dead or a xenomorph by now, c'mon, we can't wait here forever. Other marines have been picking up non-xeno movement ever since we got here, it's not just us and the xenos. Take this."
William tears the duct tape holding his motion tracker on his rifle off and hands the tracker to George.
"It's a motion tracker, point it somewhere and it tells you if something is moving. Nothing can escape it."
As they begin walking, William turns around and says "Oh, don't stand near the vents, either, unless you have a death wish."