Questions & Answers about Vad brukar du slarva med?
Why is the preposition med placed at the very end of this question?
Just like in casual English ("What are you careless with?"), Swedish normally leaves the preposition at the end of a question rather than putting it before the question word. This is the standard way to ask vad (what) or vem (who) questions in everyday Swedish.
Could I put med at the beginning and ask "Med vad brukar du slarva?"
Grammatically yes, but it sounds very stiff and formal. In everyday Swedish, you should almost always leave the preposition at the end of the sentence (called preposition stranding) rather than moving it to the front.
Why is the verb slarva in its infinitive form instead of the present tense slarvar?
Because it follows the verb brukar (to usually do something). Just like with other auxiliary verbs (like kan or vill), brukar forces the following verb into the infinitive form, and you don't use att (to) between them.
Does the verb slarva always need the preposition med?
Not always, but they are a very common pair. By itself, slarva just means to act carelessly or to be sloppy. When you want to specify exactly what you are being sloppy with (like your homework, your diet, or your spelling), you must use slarva med.