I took mathematics and physics because I think that ________ very important for me to make further research in this field.
Passengers are permitted __________ only one piece of hand luggage onto the plane.
Simon made a big bamboo box __________ the little sick bird till it could fly.
Today we have chat rooms, text messaging, emailing...but we seem __________ the art of communicating face-to-face.
As a punishment she was not permitted __________ part in any school activity in a week.
I hurried to the airport only __________ the plane I was to take had just taken off.