(A) have discovered the principles of solar energy whenever fuel becomes scarce and expensive but will forget
(B) have discovered the principles of solar energy whenever fuel has become scarce and expensive but they forget
(C) discovered the principles of solar energy every time fuel becomes scarce and expensive, forgetting
(D) discover the principles of solar energy every time fuel became scarce and expensive, but they forget
(E) discover the principles of solar energy whenever fuel becomes scarce and expensive but forget
Solution:
Pronoun + Parallelism
A: “…have discovered…but will forget…” is not parallel.
B & D: “they” incorrectly refers to “principles”.
C: It suggests that people forget “the principles” while discovering them. Illogical.
E: Best choice. Maintains parallelism through “People discover the principles…but forget them…”
Sentence Correction - 1000 Questions with Solution:
