蚕

1. Origins, structure, and basic meaning

• Structure: The spelling is 蚕, read かいこ, and it is a noun for the caterpillar that eats mulberry leaves and spins a cocoon.
• Basic usage: 蚕 means a silkworm raised for the cocoon from which silk fiber is obtained.

2. Common pitfalls and similar expressions

• An observed animal and a past experience of raising it
  • Both examples use the form 蚕. The class observes silkworms eating mulberry leaves, while the grandmother describes having raised them herself at home in the past.
• Mulberry leaves in class and silkworms raised by a grandmother
  • 桑の葉を食べる蚕を教室で観察した。 — We observed silkworms eating mulberry leaves in class.
  • 祖母は昔、家で蚕を育てていたと話した。 — My grandmother said that she once raised silkworms at home.