1 —When did you come back from Beijing?
—_____ the morning of April 18th
A:At B:Within
C:On D:In
2 There will be many famous paintings________this Sunday.I'll go and appreciate them.
A:on show B:on duty
C:on watch D:on business
3 The children had their besutiful clothes _______bacause it's Children's Day.
A:in B:on
C:with D:over