Do you like eggs ______ breakfast? [ ]

Did you enjoy your tour around Beijing， Mr Singh？—Yes. But I hate 　　　　 when the tour guide held out his left hand to shake hands with me.

The art exhibition is really worth _______，and you’re sure to learn lot from it.

The old scientist devoted most of his time ___________ the space science.

What about this dress? — I don’t like the colour. Please show me ______ one.