Tours are designed to keep travelers safe.

Identify the type of verbal used in the sentence and the word it modifies.

infinitive: "designed"

infinitive: "travelers"

participial: "tours"

gerund: "safe"

The correct answer is: Infinitive: "designed"

In this case, the infinitive phrase "to keep" is used as an adverb and it modifies the word "designed."

Oftentimes, infinitive starts with "to" plus the verb. On the other hand, gerunds end a verb with "-ing" while participial are present participles.