Question

police is investigating the case ..phrasal verb of investigating​

Answer 1

Answer:Verb-preposition combinations are tricky. “Looking into" is a two-part verb [roughly equivalent to investigating] which requires the syntax of a verb and a prepositional phrase [despite the fact that the verb and preposition semantically form a verb]. “Looking into" is not a separable verb, a different verb-preposition construction that sometimes puts the object between the verb and preposition, as “they were looking the situation over". Why I can't say. It's just how it is. “Looking into" [investigating] is a two-part verb; “looking over" [examining] is a separable verb. They have different syntax.

Explanation: