There's a bed in front of the desk.  CORRECT!

There's a bookshelf nest to thesofa
>> There's a bookshelf next to the sofa.
Explanations: Be careful with the spelling of the words that you use in your sentences. Don't forget to put space between two different words. Always remember to put period to close your sentence.

there's a computer behind the cheir
>> There's a computer behind the chair.
Explanations: Please, be careful on your spellings and put period to end a sentence.

COMMENT:
 Very Good!
Thank you very much Abraham for sending me your homework. Please take note of the corrections I gave you and avoid them next time. I can see that in your young age you were able now to make long sentences to clearly convey your ideas. Please keep it up and see you!
-Teacher Joanna ^_^