Once in a blue moon My sister lives in Alaska, so I only see her once in a blue moon.

Earthquakes result in a great loss of life.

intriguing. These discoveries raise intriguing questions.

in the nick of time

Lock horns = debate, argue, have row with locking horns (noun) = debate, argument The mayor and her deputy locked horns over plans for the new road

The landlord was very generous to us. All that we consumed in his inn was on the house.

We must reach Khartoum at any cost.

take on. There’s so much work to do in the office that maybe we should take on a secretary.

come under fire The minister came under fire for his rash decision to close down the factory.

insensitive. She's completely insensitive to my feelings.

Stand in for. Mr Horrid will be standing in for Mrs White while she’s ill.

up in the air

In the light of recent incidents, we are asking our customers to take particular care of their personal belongings.