1. There isn't a pen on the table.
Is there a pen on the table?
肯定回答: Yes, there is.
否定回答: No, there isn't.
2. There aren't two pencils on the table.
Are there two pencils on the table?
Yes, there are.
No, there aren't.
祝你学习进步,更上一层楼! (*^__^*)
不明白的再问哟,请及时采纳,多谢!