I'd rather spend the vacation in his house watching tv with him.
I'd rather spend the vacation at his house watching tv with him.
Are both the above sentences grammatically correct?
I'd rather spend the vacation in his house watching tv with him.
I'd rather spend the vacation at his house watching tv with him.
Are both the above sentences grammatically correct?
In general, you would use at - his house is a place on a map, and you want to be at that place.
I love hanging out at Doug's place. He has a pool, and tennis court, and a huge television. He suggested we go to Vegas over the break, but I'd rather spend the vacation at his house watching tv.
The exception would be if you are really wanting to emphasize that you want to be indoors, as opposed to in his yard or on his patio:
Doug asked me to come over and help him reshingle his roof. It is too hot for that sort of activity. I'd rather spend the vacation in his house watching tv.