The United States has emitted more greenhouse gases than any other country in the world，and has reaped （）economic benefits from those emissions.

-Serina has been watching the TV series the whole night.-（）.

A.So her parents have
B.So have been her parents
C.Her parents have been so
D.So have her parents

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I was just beginning（）asleep when the phone rang.

A.fall
B.falling
C.to fall
D.being fallen

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