投入

1. Origins, structure, and basic meaning

• Structure: 投入 is read とうにゅう and means putting or deploying equipment, people, or other resources where they are needed.
• Basic usage: It is used for a factory putting new machinery into use or a player being brought on in the second half of a game.

2. Common pitfalls and similar expressions

• Deploying and being deployed
  • 機械を投入した describes the action of the party introducing the machinery.
  • 選手が投入され is passive wording for a player being brought on.