--I’m worried about my English. -- ______ harder ________ you will catch up with your classmates.

– David’s seldom late for school, ______ he? -- ______, even though the weather is very bad.

I won’t believe that the five-year-old boy can read magazines ____ I test him myself. 

—Mr Wang’s never been to Canada, has he?— ______. He went there on business last week.

—Lisa didn’t come to school yesterday, did she ?--________ , though she was not feeling very well.