"I is" or "I was" or "It is"?

Senin petang, 9 April, putra sulung Ivan mengerjakan PR bahasa Inggris dari buku: Stairway A Fun and Easy English Book for Grade IV of Elementary School, terbitan Platinum (PT Tiga Serangkai Pustaka Mandiri), Chapter When Were You Born? page 172. Kemudian Ivan bertanya karena tidak memahami maksudnya. Setelah saya pelajari, sayapun tidak bisa memahami. Soal ini saya posting di Facebook, untuk meminta pendapat dari teman yang berkompeten: My boy have a homework. Examples in the book only: a. When were you born? I was born ... b. When is your birthday? It is ... But in practice questions like the following picture Why the answer is "I is ..." Thank you Berikut respon dari beberapa teman, antara lain: Putu Sukmaantara – Dosen Prodi Bahasa Inggris FKIP Universitas Jember. “I've commented your picture, Sir. That exercise is totally incorrect. I'm sure you know the answers. For no. 1, the answer should begin with 'It is ...'; and it is incorrectly typed, THEN, to make it worse, that is then copied and pasted without rechecking it first.” Alimah Hidayati – Guru Kelas SBI di SMP Negeri 3 Jember. “Wah..dr buku mana ini pak? Seumur2 sy br skl ini ketemu I is..yg sy tau I am, I was born..” Demikian, pendapat beberapa teman yang kompeten di bidang bahasa Inggris. Saya sudah mengakses situs penerbit PT. Tiga Serangkai (http://www.tigaserangkai.com/), tapi tidak terdapat tautan (link) email.