This is his pencil sharpener 改为一般疑问句和否定句怎么改?

This is his pencil case. this is his pencil case 复数句 This is his pencil.(改为否定句) This is my pencil.（改为复数句） It's his backpack.（改为复数句） --- () is this?--It's a pencil This is his pencil-box.改为复数句子怎么改? 将this is his pencil改为一般疑问句 This pencil case is his 改为同义句 is that your a book?哪里错了This is a pen and that's a ruler?Is this his pencil?哪里错了!求 This is his red pencil改为同义句 （ ）（ ）a red pencil This is his red pencil改为同义句 （ ）（ ）a red pencil. This color pencil is (Li Lei's)(括号提问)this color pencil this is your pencil This is Lisa's pencil sharpener.改一般疑问句 IS this his book?改为复数句 This is my pencil.改为同义句 This is his pencil case改为一般否定句 This is my eraser 改为否定句 This is his pencil case改为一般否定句 This is my eraser 改为否定句 This color pencil is Li Lei's 就Li Lei's 提问 ,___________ ___________ this color pencil?