"Esta es mi casa en el invierno."
Translation:This is my house in the winter.
Sounds funny to me to leave out the 'the'; this is my house in summer, this is my house in fall and etc. but that's just me, and another input. I would be more likely to say this is my winter house (home) etc. But I did loose a heart because I wrote it in half English and half Spanish. HaHa!
I got it right because I know duo. I wanted to say "this is my winter home", but thought it would not accept it.