

Du musst dich zuerst online registrieren.
[ˈduː ˈmʊst ˈdɪç tsuˈʔeːɐ̯st ˈɔnlaɪ̯n reɡɪsˈtriːrən.]
You have to register online first.
Ich habe mich gestern auf der Webseite registriert.
[ˈɪç ˈhaːbə ˈmɪç ˈɡɛstɐn ˈaʊ̯f deːɐ ˈvɛpz̥aɪ̯tə reɡɪsˈtriːɐ̯t.]
I registered on the website yesterday.
Registrieren Sie sich bitte an der Rezeption.
[reɡɪsˈtriːrən ˈziː ˈzɪç ˈbɪtə ˈan deːɐ retsɛpˈtsi̯oːn.]
Please register at reception.
"registrieren" is in the lesson "Verbs 15" (Level 27), along with 11 other useful words. LinDuo has 180 topic lessons like this one, 2,375 words in total. Every word has an illustration, a transcription and pronunciation in a female and a male voice. Just 10–15 minutes a day is enough to learn them all. Free, and works offline.