Many parents want their children to learn a second language. French immersion programs in Canada allow kids to do that but a few schools give kids the opportunity to learn a third or even fourth language either during regular class time or an after-school program.
If an adult really wants to learn a language, total immersion and the passion to learn it are the most important premisses to succeed. The suggestion made by Ellen Bialystock is meant for people who want to learn a new language “at home”, who don’t have the opportunity to learn it in loco. But if we have to learn the language because we move to the country, it’s more probable that we will attain a very good fluency in a very short time. If total immersion is not possible, there are many other possibilities to create a monolingual exposure in the language we want to learn in real life or online or via skype etc.