---Why are you so disappointed？
---I went there hurriedly and waited there for 3 hours，______ the tickets have been sold out．
A. only to be told B. only to tell
C. telling D. being told
We can hardly believe such a young boy_______ travel around the world all by himself.
A. may B. need
C. should D. must
President Xi Jinping demanded the environmental problems _______paid special attention to.
A. referred to be B. referred to being
C. refer to being D. refer to be
--- Haven’t seen you for ages! Where have you been ?
--- I went to Ningxia and _______ there for one year, teaching as a volunteer.
A. have stayed B. stayed
C. had stayed D. am staying
It was only after we had watched the film "Amazing China"_______ we realized what amazing achievements China has made in the past five years．
A. when B. that
C. which D. what
_______ the global economy is showing signs of recovery, many developing countries are still suffering.
A. While B. Where
C. How D. As
