(adj.) producing a wanted or intended result
effective
(n.) a sound that bounces off a surface and returns to the listener
echo
(adj.) exactly the same
identical
(v.) to copy the words or actions of someone or something
imitate
(n.) a thing needed to make something or to do an activity
material
(n.) a smaller copy of something, often used to show what the actual thing looks like or will look like after it is built
model
(v.) to watch or listen to someone or something carefully
observe
(adj.) alike but not exactly the same
similar
(adj.) normal or usual; not special
ordinary
(v.) to find where something is
locate
(v.) to move back and forth or from side to side with very short, quick movements
vibrate
(v.) to find one's way to a place, especially along a planned course or route
navigate
