Above: The Dual NDVI Ultra Probe Unit is powered by a Nano Logger (enhanced by an array of beryllium spheres) and is ready for field action. The TSL2561 is a common luminosity sensor. It measures how bright it is and reports in units that relate to the brightness that people perceive (lux).
An adjective describes (tells us more about) a noun or a pronoun. For example: student is a noun. But we can say more about the student in our sentence by using an adjective: intelligent student; clever student; lazy student; good student... etc. So, here is a sentence: The teacher says Marie is a good student.
The purpose of an essay is to encourage students to develop ideas and concepts in their writing with the direction of little more than their own thoughts (it may be helpful to view the essay as the converse of a research paper). Therefore, essays are (by nature) concise and require clarity in purpose and direction.