"The people speak Dutch in Amsterdam and they use a bicycle."
Translation:Labhraíonn na daoine Ollainnis in Amstardam agus úsáideann siad rothar.
The Irish for "in" is i.
The Irish for "in the" is sa.
As both of these forms end with a vowel, they take an additional n when they come before a word that starts with a vowel sound - in áit éigin, san áit sin.
(There are a few other places where in is used, but they're a bit more advanced).