Hertz measures cycles per second - one Hertz is one cycle per second. Unlike gauss that is a measurement unit for the strenght of a specific thing (an electromagnetic field), hertz is a generic frequency measurement.
Prepend is a word that means to attach content as a prefix. It is often used in different kinds of programming and in automated processes. Some prepending is done manually as a user. For example, a prepend command could be used in a scripting language that a programmer would enter into a certain function or code module. It would add certain characters of text to the beginning of some variable or object.
A preposition is a word which precedes a noun (or a pronoun) to show the noun's (or the pronoun's) relationship to another word in the sentence. (The word preposition comes from the idea of being positioned before. preposition sits before a noun to show the noun's relationship to another word in the sentence. Examples: For native English speakers, grammatical errors involving prepositions are rare. The most common errors involving prepositions are shown on the right.