"With this you can see stars and dreams."
Translation:Hiermee kunnen jullie sterren en dromen zien.
This website has a few pages that can explain why "Many Dutch pronouns do not allow a preposition before them.".
This site is a great reference that will help you with much more Dutch as well. I use it almost every time I study.
Let me know if this helps or if you need a better explanation. :)
Basically, when the 2nd person sing. pronoun is used in front of the verb, then the 'normal' verb form is used (so usually stem+t, in this case kunt)
When the je/jij pronoun comes after the verb, then we use the verb form of the first person singular (so usually the stem, in this case kun)
So: Je bent er eindelijk. vs Eindelijk ben je er. Je vindt het vervelend. vs. Vind je het vervelend?