How to make mushroom barley soup<br>Chop the vegetables. Wash 1 pound (480 g) of mushrooms , 2 large carrots , 2 large celery stalks, and peel 1 onion. Use a sharp knife to carefully cut the mushrooms into 1/2-inch (12 mm) pieces.
mushrooms have to be cut in a certain way. 
 According to the text, you need to carefully cut the mushrooms into 1/2-inch (12 mm) pieces.

( z1 obligate :ARG2 ( z2 cut :ARG1 ( z3 mushroom ) :manner ( z4 way :mod ( z5 certain ) ) ) )