half a day

I clean the room.

私は部屋を掃除します

I clean the room for half a day.

私は半日部屋を掃除します

I clean the room at home for half a day.

私は家で半日部屋を掃除します

I clean the room at home with my younger brother for half a day.

私は弟と家で半日部屋を掃除します

I clean the room at home with my younger brother for half a day today.

私は今日弟と家で半日部屋を掃除します