"You are giving them his/her books !" = "Anda sedang memberikan buku kepada mereka!" Buku = Book Rumah = House

"You are giving them his/her books !" "Kamu memberikan buku-buku dia kepada mereka!" or "kamu memberikan kepada mereka buku-buku dia!" "books" (english) with "s" ---- plural || In bahasa means 'jamak' || so 'books' means --- buku-buku not 'rumah', rumah in english is 'house'... "giving" --- verb-ing / continous tense in bahasa that means "yang sedang berlangsung" but, in bahasa, is not always use word "sedang" for continous tense.. like what Rina's comment above, she put a word "sedang" in a parenthesis, it means you can use it or no... it is up to you..

"Anda (sedang) memberikan buku-buku dia kepada mereka!"