To Imagine
する verb
To do a concept of an image (in your mind) would require you to imagine it, because it's just a concept and not real.
そうぞうする
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
コウイチは仕事中、たまに想像できないような動きをする。
Every once in a while Koichi will move in an unimaginable way while he's working.
てらや神社をめぐってごしゅいんちょうにごしゅいんを集める仕事って、想像できる？
Can you imagine having a job where you visit temples and shrines to collect their red ink stamps in a book?
もし指を喉に突っ込む以外でゲロを吐く方法を学びたいなら、裸のコウイチを想像するといいよ。
If you want to learn how to vomit without sticking your finger down your throat, just imagine Koichi naked.