The employer, not the sales boy and his partner ........ responsible for the loss

Analyze the question: This tests subject-verb agreement, specifically the rule about phrases like "not... and...".

Concept: When a subject is followed by a negative phrase such as "not X," "as well as," or "together with," the verb agrees with the main subject (the one before "not"). The negated part is only a parenthetical addition and does not change whether the verb is singular or plural.

Solution:

1. Find the main subject: "The employer". It is singular.
2. The phrase "not the sales boy and his partner" is only a contrast. Even though it contains "and", it does not make the subject plural.
3. A singular subject takes a singular verb, so we need "is".

Check each option:

• A. are is plural, so it is wrong.
• B. are being is plural, so it is wrong.
• C. are never is plural, so it is wrong.
• D. is is singular and agrees with "The employer", so it is correct.

Complete sentence: "The employer, not the sales boy and his partner, is responsible for the loss."

Exam tip: In JAMB, when you see "not," "as well as," "together with," or "along with," cover that phrase with your finger. Then match the verb to the subject that remains. Here, "The employer ___ responsible" clearly needs "is".