Be careful,________ you'll make fewer mistakes in the exam.( )
A.orB.butC.and
--________ does your father visit your grandparents a week? –Once.
-- ______ you______ your homework yet? --Yes, I _____ it just now.
--_____ you ever ____ to Beijing? -- Yes, I went there last year.
---Isn’t the trip boring? --- . I’d like to sleep at home instead of going out.
-____you ever ____with a group? -Yes, I have .