The particle in a phrasal verb always functions as the head of the phrase, determining the tense and the agreement of the verbal construction with the subject.

In three-part phrasal verbs (verb + adverb + preposition), such as "look forward to," the particles are always separable and can be moved to the beginning of the sentence for emphasis.

Intransitive phrasal verbs, such as "break down" or "show up," necessarily require a direct object to be grammatically correct in formal written contexts.

Transitive phrasal verbs can be separable, meaning that the direct object can be placed between the verb and the particle, especially when the object is a personal pronoun.

The meaning of a phrasal verb can always be deduced by the literal sum of the meanings of its individual parts, making dictionaries unnecessary for advanced learners.