Class 7

What are the types of construction?

Constructions and buildings are usually classified into one of the five basic types according to their construction type: Type I (or Type 1) – Fire-resistive construction. Type II (or Type 2) – Non-combustible construction. Type III (or Type 3) – Ordinary construction. Type IV (or Type 4) – Heavy-Timber construction.

Are customers singular?

Nouns in singular always need an article: A customer, a problem (if both are unknown at the time of speaking). Most likely (I hope) each customer will have a single problem, so I would use “If a customer has a problem …” The double plural “If customers have problems” is grammatically correct.