Question

which sentence includes a gerund?
o sarah was diving into the lake from the raft all afternoon.
o we were hiking alongside the river last saturday.
o walking three miles is an excellent form of daily exercise.
o singing lessons had been a dream of hers for years.

Explanation:

A gerund is a verb - form that functions as a noun and ends in - ing. In "Walking three miles is an excellent form of daily exercise", "walking" is the subject of the sentence and is a gerund. In "Sarah was diving into the lake from the raft all afternoon" and "We were hiking alongside the river last Saturday", "diving" and "hiking" are parts of the past - continuous verb tenses. In "Singing lessons had been a dream of hers for years", "singing" is an adjective modifying "lessons".

Answer:

Walking three miles is an excellent form of daily exercise.