"those" (l.13) refers to "contexts" (l.13).

"readily" (l.14) is synonymous with promptly.

"much" (l.1) can be replaced by many.

English learned in Australia can be considered a foreign language.

if you are English and you are learning Portuguese in Brazil, Portuguese will be a second language for you.

a second language is that one you learn in a foreign country where this language is the native language.

even when we are preparing our curriculum or a lesson, the difference between a second and a foreign language is not relevant.

teachers usually make no difference between second and foreign language.

"better" (l.7) is the opposite of worse.