Diachronic (according to Merriam Webster) means:
of, relating to, or dealing with phenomena (as of language or culture) as they occur or change over a period of time.
Synchronic (also according to Merriam Webster) means:
concerned with events existing in a limited time period and ignoring historical antecedents.
While the two may seem, on the surface, very similar, there is one distinct difference: historical consideration.
What this means is, synchronic looks at a specific event in regards to the event alone. Nothing that has led up to the event, or following the event, is taken into consideration. Diachronic, on the other hand, looks at the entire picture: everything that has relation to why something changes over time.
For example, language can bee looked at either diachronically or synchronically. If looked at diachronically, one would consider the races of people, the nationalities, the education level, and the use of slang when determining the phenomena regarding how language changed in the South over time.
If one were to look at language synchronically, they would only look at one period of time, which they were interested in, and why the language exists as it does based solely off of the time period alone.
Basically, in simple terms, diachronic uses all resources to examine something, whereas synchronic looks at a very limited aspect of the information based upon a singular ideal.
As for teaching examples, if teaching diachronically, the students would learn about the period, the characteristics of the period, the history of the period, the influences of the period, and so on. If teaching synchronically, the work would simply be examined as a text alone; no consideration would be given to the period, the history, or any other events which surrounded the author and time period which the writing took place.
A quick example: The Diary of Anne Frank
synchronic focus - just on Anne Frank and her family's experiences in the annex, possibly as a literary focus on character motivation or conflict.
diachronic focus - understanding the background of Hitler's rise to power, the impact of WWI, gobal economics, and anti-Semitism and how these events led to and shape the story of Anne
Thanks for answering! The thing is I am from Argentina and those are appraches we've learnt to teach English as a second language. Maybe that's why you don't know them. Thanks anyway! Your previous answer was pretty much clear for me!
Thanksss! The thing is I'm studying to be a teacher, and they are asking me this regarding approaches like CLIL, CLT, TPR, Suggestopedia, and so on