(February 2013) Durham tubes are used in microbiology to detect production of gas by microorganisms. They are simply smaller test tubes inserted upside down in another test tube. This small tube is initially filled with the solution in which the microorganism is to be grown.
A compound predicate is two or more simple predicates joined by a conjunction that indicate actions by the same subject. Example : Bill picked up the mail and walked the dog.. Bill is the subject for both verbs.
The compound noun is just a noun that has been formed through the conjunction of two English words. Structurally, the compound noun is usually formed through a noun plus a noun, or an adjective plus a noun. For example, bedroom is a compound noun formed by the nouns bed and room. Examples & Rules. Here is an example for you of the compound noun being used correctly within a sentence.