Do you know the reason _________ pilotsturn off the plane’s lights before taking off —The practice is for the passengers toadjust to the dark _________ an emergency.

The government must be very _____ about settingpolicies and make no decision until they are quite sure it is the right one

Scientists have been the temperature of the oceans to see how it changes over a period of time.

It was a nice meal, __________ a little expensive

Mr. Smith works with an auto company, but he _________ for this industrial exhibition, since he is on leave.[ ]