Several years ago I was in Germany visiting my aunt who was terminally ill in a hospice. One of her nurses was Polish and told us she’d been in Germany for over 20 yeas. She would have been in her 40s at the time so would have left Poland in her 20s. She said that after spending so long in Germany and not being surrounded by Poles, she’d forgotten how to speak Polish properly because its so complicated and despite living in Poland for the first 20 odd years of her life, she now could not communicate properly in what was once her native language.