which sentence or sentences have correct parallel structure?\n\ndesert animals must develop adaptations that…

which sentence or sentences have correct parallel structure?\n\ndesert animals must develop adaptations that not only allow them to deal with extreme heat but also help them to cope with a lack of water.\n\ndesert animals must develop adaptations that allow them not only to deal with extreme heat but also to cope with a lack of water.

which sentence or sentences have correct parallel structure?\n\ndesert animals must develop adaptations that not only allow them to deal with extreme heat but also help them to cope with a lack of water.\n\ndesert animals must develop adaptations that allow them not only to deal with extreme heat but also to cope with a lack of water.

Answer

Brief Explanations:

Parallel structure requires that items joined by correlative conjunctions like "not only... but also" follow the same grammatical form.

  1. In the first sentence, "not only" is followed by a verb phrase ("allow them to deal..."), while "but also" is followed by a different verb phrase ("help them to cope..."). Both sides are grammatically consistent as complete predicate phrases following the relative pronoun "that."
  2. In the second sentence, "not only" is followed by an infinitive phrase ("to deal with..."), and "but also" is followed by a matching infinitive phrase ("to cope with..."). This creates a perfectly balanced structure.

Both sentences maintain grammatical symmetry between the two parts of the correlative conjunction.

Answer:

Both sentences have correct parallel structure:

  • Desert animals must develop adaptations that not only allow them to deal with extreme heat but also help them to cope with a lack of water.
  • Desert animals must develop adaptations that allow them not only to deal with extreme heat but also to cope with a lack of water.