Translation:The cat seems to want to play with the string.
Is there a trick to know when to use Vill or Vilja? I got that vill ha is when you want an object or food, so does vilja have a similar rule?
"Vilja" is the infinitive form of "Vill".
Infinitive is a form of verbs that have many uses, one of them being that they are used after modal and auxiliary verbs.
English has infinitives as well, with similar usage as Swedish, but ours are harder to distinguish because they usually appear exactly the same as the present tense.
One way to distinguish between infinitives and present tense in English is to say the same sentence, but with a singular pronoun like "He/She", if the verb has an -S at the end, it's present tense.
For example, "Gå" is the infinitive of "Går":
"I go" -> "Jag går"
"She goes" -> "Han går"
"I can go" -> "Jag kan gå"
"He can go" -> "Han kan gå"
Different construction, that's Det verkar som att katten vill leka med snöret.
So the difference is that the cat has to be the subject in the sentence OK tack
Yup, we just like to try to keep the translations as close as possible (without becoming unnatural). Since Swedish and English are very similar, it's usually – but not always – possible to construct things the same way.