How the word "klopfen" is translated into English
Du musst an die Tür klopfen.
[ˈduː ˈmʊst ˈan ˈdiː ˈtyːɐ̯ ˈklɔpfn̩.]
You have to knock on the door.
Kannst du bitte leiser klopfen?
[ˈkanst ˈduː ˈbɪtə ˈlaɪ̯zɐ ˈklɔpfn̩?]
Can you please knock more quietly?
Du sollst nicht ans Fenster klopfen.
[ˈduː ˈzɔlst ˈnɪçt ˈans ˈfɛnstɐ ˈklɔpfn̩.]
You shouldn't knock on the window.
"klopfen" is in the lesson "Verbs 6" (Level 18), 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.