Intransitive verbs take no objects or complements.
Nothing receives the actions of talking and going in these sentences, so the verbs are intransitive. Such verbs may have adverbial modifiers. In the preceding sentence, in the straightaway is a prepositional phrase modifying the verb accelerated.
Transitive vs. intransitive
The dictionary will tell you whether a verb is transitive or intransitive. Some verbs have both transitive and intransitive functions.
TRANSITIVE
INTRANSITIVE
In the first example, flew has a direct object that receives the action: her plane. In the second example, the verb is followed by an adverb (overhead), not by a direct object.
Exercise:
Linking, transitive, and intransitive verbs
Related topic:
Transitive verbs