English grammar – Spot the error (choose the part with an error or “No error”). Condition pattern: We can not handle / this complicated case today / unless full details are not given / to us by now.

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:

• Main clause: inability to handle the case today.
• Condition: presence/absence of “full details.”
• Temporal phrase: “by now.”

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:

Verification / Alternative check:

Why Other Options Are Wrong:

Common Pitfalls:

Final Answer:
unless full details are not given