Example 1
Blaine and Margaret take a limo to school every morning.
How fancy! Equally fancy is the subject-verb agreement in this sentence. Since Blaine and Margaret is a compound subject connected by and, the plural verb take is the way to go here.
Example 2
Black mambas and boomslangs make terrible pets.
These snakes are two of the deadliest in the world. In fact, some zoologists have dubbed the black mamba "death incarnate." Scary. What's not scary is the subject-verb agreement in this sentence. Since mambas and boomslangs is a compound subject, the correct form of the verb is make.
Example 3
Bangers and mash are two staples of English pub grub.
In America, we'd call them sausages and mashed potatoes, but we think this sounds much cooler. We think the subject-verb agreement in this sentence sounds equally cool. Bangers and mash is a compound subject, so the plural verb are is the right choice.