(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.
Simple Sentence: A sentence with a simple subject and predicate. The flower is red.. Compound: A sentence made up of two or more simple sentences joined together by a comma and a conjunction. I tried to speak Spanish, and my friend tried to speak English.. Complex: A sentence consisting of two sentences joined together in a way that once sentence explains another.