------Mum,can I go out to play with Tom for just a while ? ------ _______ and do what you like.
Do you remember the day ________ we played all day along the seaside?
The country's railway system has launched online ticket-booking and a real-name ticket purchasing system, and _______ requires passengers to provide their ID numbers when buying tickets.
It’s time you changed your attitude _____ women now, Tom; they hold up half the sky, you know.
— Shall Mary come to the concert with us?-Not_____she has finished her paper.
Many a student _____ that mistake before.