I can’t go to the New Year’s concert,_____,100 dollars is just too much for me to spend in one evening.

His first lecture is of great use to our development. But his latest one is ______ worth attending.

Now young people like to go to the fast-food restaurant,____ ,as the name says,eating doesn’t take much time.

Why is he so happy—He __________ the volunteeringclub and works for the old people.

Li Na plays _______ tennis very well. She becomes (成为) _______ first Asian woman to reach a Grand Slam (大满贯).