Visible light waves are the only electromagnetic waves that the human eye can see. These waves are visible as the seven colors of the rainbow known as red, orange, yellow, green, blue, indigo and violet.
Since none has the meanings ânot oneâ and ânot any,â some insist that it always be treated as a singular and be followed by a singular verb: The rescue party searched for survivors, but none was found. However, none has been used with both singular and plural verbs since the 9th century.
The indefinite pronoun none can be either singular or plural, depending on its context. None is nearly always plural (meaning not any) except when something else in the sentence makes us regard it as a singular (meaning not one), as in None of the food is fresh..