Which sentences below include only prepositional phrases (no participial or absolute phrases and no dependent clauses)?
select all that apply.
then one, and then another of the boys carne up on the far side of the barrier of rock, and he understood that they had swum through some gap or hole in it.
there was no one visible; under him, in the water, the dim shapes of the swimmers had disappeared.
he could see nothing through the stinging salt water but the blank rock.
when he carne up, the boys were all on the diving rock, preparing to attempt the feat again.

The sentences that include only prepositional phrases are "There was no one visible; under him, in the water, the dim shapes of the swimmers had disappeared" and "He could see nothing through the stinging salt water but the blank rock".

Explanation: A prepositional phrase is a group of words introduced by a preposition. Generally, a prepositional phrase also includes a noun or a pronoun. The sentence "There was no one visible; under him, in the water, the dim shapes of the swimmers had disappeared" contains two prepositional phrases: "under him" and "in the water", which have been introduced by "under" and "in" respectively. Furthermore, in the sentence "He could see nothing through the stinging salt water but the blank rock", "through the stinging salt" is a prepositional phrase since it begins with the preposition "through".

faulty parallelism is a construction in which two or more parts of a sentence are equivalent in meaning but not grammatically similar in form.

the correct version of this faulty parallelism in the sentence is:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.

the problem is the last sentence, the first two have a basic subject+verb+object structure.

so, to give a proper balance to the structure, or better said, to give a parallel structure, we must write a basic s+v+o structure in all three sentences:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.