Difficulty: Easy
Correct Answer: unless full details are not given
Explanation:
Introduction / Context:This sentence tests correct use of “unless,” which means “if not.” Adding another “not” creates a double negative and reverses the intended meaning.
Given Data / Assumptions:
Concept / Approach:“Unless” inherently carries negation, so the subordinate clause should be affirmative: “unless full details are given.” If you add “not,” the meaning shifts to “if full details are not not given” (i.e., if they are given), producing the opposite of what is intended.
Step-by-Step Solution:
Replace Part C with “unless full details are given”.Retain Parts A–B as they state the main claim properly.D is awkward with “by now” (today vs. now), but not the core grammatical error; the test focuses on the misuse of “not.”Verification / Alternative check:
Improved: “We cannot handle this complicated case today unless full details are given to us.”Why Other Options Are Wrong:
A–B are grammatically fine; D is stylistically clumsy but acceptable; C contains the genuine grammar fault.Common Pitfalls:
Using “unless … not …”; mixing time adverbials (“today” vs. “by now”).Final Answer:unless full details are not given
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