this is a pencil-box这个句子有什么错

this is a pencil-box这个句子有什么错 This is a pencil box.对a pencil box 提问 This is a pencil box.(对” a pencil box”提问 ) （ ）pencil-box is this?填什么 This is his pencil-box.改为复数句子怎么改? This is a pencil box 改为一般疑问句 this is a new pencil-box改我一般疑问句 is this her pencil box?改为陈述句 is this your pencil-box?的答语 Is this pencil box?(改为陈述句) 改为复句this is my pencil box A pencil box is in C____ 906.在空处填什么?