Explanation Text

1.       The Purpose

To explain the processes in the formation or workings of natural or siciocultural phenomena

2.       Generic Structure

A.      A general statement to position the reader.

B.      A sequenced explanation of why or how something occurs

3.       Lexico Grammatical

A.      Focus of generic, non-human participants.

B.      Use mainly of material an relational processes

C.      Use mainly of temporal and causal circumstances and conjuctions

D.      Some use of passive voice to get theme right

Example :

A flare is defined as a sudden, rapid and intense variation in brightness. A solar flare occurs when magnetic energy, built up in the solar atmosphere is suddenlly released. Radiation is emitted across virtually the entire electromagnetic spectrum, from radio waves at the long wavelength end, through optical emission to X-rays and gamma rays at the short wavelength end.

As magnetic energy is being released, particles, including electrons, protons and heavy nuclei, are heated and accelerated in the solar atmosphere. The energy released during a flare is typically on the order of 1027 ergs per second. Large flares can emit up to 1032 ergs of energy. This energy is ten million times greater than the energy realesed from a volcanic explosion. On the other hand, it is less than one-tenth of the total energy emmited by the Sun every second.

There are typically three stages to a solar flare. First is the precursor stage, where the release of magnetic energy is triggered. Soft X-ray emission is detected in this stage. In the second or impulsive stage, protons and electrons are accelerated to energies exceeding 1 MeV. During the impulsive stage, radio waves, hard X-rays and gamma rays are emitted. The gradual build up and decay of soft X-          rays can be detected in the third,  decay stage. The duration of these stages can be as short as few seconds or as long  as an hour.

Exercise

Photosynthesis is a very complex process and for the sake of convenience and ease of understanding, plant biologists divide it into two stages.

In the first stage, i.e. the light-depedent reaction, the chloroplast traps light and converts it into chemical energy contained in nicotinamide adenine dinucleoide phosphare (NADPH) and adenoside triphosphete (ATP), two molecules used in the second stage of photosynthesis.

In the second stage,called the light independent reaction (formerly called the dark reaction), NADPH provides the hydrogen that helps form glucose, and  ATP provides the energy for this and other reactions used to synthesize glucose.

These two stages reflect the literal meaning of the term photosynthesis tobuild with  light energy

1.  Do you know the important party of tree in which the process of photosynthesis occurs?

2.   Have you studied how the photosynthesis works? Explain it as simples as possible.

3. What is the purpose  of the text?

4. Make generic structure of the text!

5. What tense used in the text and give the example