Nelson Mandela, former president of South Africa, devoted himself        to making the black and white equal.

I can’t spend___ money on the car which is ___expensive for me .

All too _____ it was time to go back to school after the glorious summer holidays.

—Are you going to Dalian by air?—No, the tickets are ____expensive for me. 

He found it hard for Alan to focus on his teachers for longer than five minutes, _________ if the lecture was boring.