Article: Effective verbal or spoken communication is dependent on a number of factors and cannot be fully isolated from other important interpersonal skills such as non-verbal communication, listening skills and clarification. Human language can be defined as a system of symbols (sometimes known as lexemes) and the grammars (rules) by which the symbols are manipulated. The word "language" also refers to common properties of languages. Language learning normally occurs most intensively during human childhood. Most of the thousands of human languages use patterns of sound or gesture for symbols which enable communication with others around them. Languages tend to share certain properties, although there are exceptions. There is no defined line between a language and a dialect. Constructed languages such as Esperanto, programming languages, and various mathematical formalism is not necessarily restricted to the properties shared by human languages. Communication is two-way process not merely one-way.

Question: What do human languages use to communicate with others?
Ans: patterns of sound or gesture for symbols

Article: The word "Imam" denotes a person who stands or walks "in front". For Sunni Islam, the word is commonly used to mean a person who leads the course of prayer in the mosque. It also means the head of a madhhab ("school of thought"). However, from the Shia point of view this is merely the basic understanding of the word in the Arabic language and, for its proper religious usage, the word "Imam" is applicable only to those members of the house of Muhammad designated as infallible by the preceding Imam.

Question: What word literally means a person who stands or walks in front?
Ans: Imam

Article: In addition to all of the above, the brain and spinal cord contain extensive circuitry to control the autonomic nervous system, which works by secreting hormones and by modulating the "smooth" muscles of the gut. The autonomic nervous system affects heart rate, digestion, respiration rate, salivation, perspiration, urination, and sexual arousal, and several other processes. Most of its functions are not under direct voluntary control.

Question: The brain and spinal cord work together to control what system of the body?
Ans: autonomic nervous system

Article: DC commutating electric motors, if fitted with laminated pole pieces, become universal motors because they can also operate on AC; reversing the current in both stator and rotor does not reverse the motor. But the now-standard AC distribution frequencies of 50 and 60 Hz caused difficulties with inductive reactance and eddy current losses. Many railways chose low AC frequencies to overcome these problems. They must be converted from utility power by motor-generators or static inverters at the feeding substations or generated at dedicated traction powerstations.

Question: How can low frequencies be obtained?
Ans:
converted from utility power