(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.
In English grammar, a compound-complex sentence is a sentence with two or more independent clauses and at least one dependent clause. Also known as a complex-compound sentence. The compound-complex sentence is one of the four basic sentence structures. The other structures are the simple sentence, the compound sentence, and the complex sentence. See Examples and Observations below.