Modern Chinese asks him to talk about why it is a structure in form. Give him a call. Why is it a concurrent structure?

"Tell him to talk" is not a formal structure, but a concurrent structure; "Call him right" is a formal structure, not a concurrent structure.

The key to distinguish these two phrases is to understand the part of speech of "jiao" here. In "call him to talk", "call" means "let" and is an imperative verb, which can be followed by a part-time word; In Tell Him Right, "Jiao" means "Bei" and is a preposition. It can only form a prepositional phrase as an adverbial with the noun or phrase behind it, which modifies and restricts the central word behind it, so it is a prepositional structure.