Grammar question (Japanese)
I have a question regarding a Japanese frase

ともだちと　たのしく　あそびます

this sentence is from a book and translated with

I enjoyed playing with my friends

I have two questions:

1. I don't know why there is this "く". Why it is "たのしく" and not "たのし"?

2. Why is "あそびます" used instead of "あそびました"?

Can someone explain it to me in English please?

Would really appreciate your help here.

Thanks a lot :)

Question

Grammar question (Japanese)
I have a question regarding a Japanese frase

ともだちと　たのしく　あそびます

this sentence is from a book and translated with

I enjoyed playing with my friends

I have two questions:

1. I don't know why there is this "く". Why it is "たのしく" and not "たのし"?

2. Why is "あそびます" used instead of "あそびました"?

Can someone explain it to me in English please?

Would really appreciate your help here.

Thanks a lot :)

Answer

Hi Tobias.
The translation is wrong because, as you noticed, it's not a past sentence.
Also, it's difficult to translate because あそびます doesn't translate exactly; it can mean 'hang out', 'play', etc. 
...AND they are using たのしくas an adverb,..  
So it means something like: "I enjoyably play/hang out with friends".. in normal English:
"I have a nice time playing/hanging out with friends",..
.. I would say.  :)

Answer

Isn't it supposed to be tomodachi ni? Not tomodachi to. Who wrote the book? A native speaker? Too many errors for a native speaker written book.
Because it's an adverb and not an adjective. Played happily, not happy.
Must be wrong translation. It's non-past tense, asobimasu is non-past form.