ls this your

ls this your school? 英语ls this your ls++this++your++school是什么意思 ls this your ruler改为复数句 ls this your backpack? 改为陈述句 ls this your computer?改为肯定陈述句 ls this your mobile作肯定回答 ls this your eraser?做出否定回答 ls this your pen?(改为肯定句） ls this your pen改为否定回答,怎么改 （ ）（ls this/are these）your picture books?yes 连词成句并翻译 your,this,ls,dog?