Only after Helen moved to Australia ______ how important she was to me .
A．I had realized B．had I realized C．I did realize D．did I realize
Spelling Bee is a contest competitors, usually children, are asked to spell as many words as possible.
A．which B．where C．what D．When
We began to open to the outside world in the ate 1970s. , there have been great changes in the country.
A．As a result of B．As a result C．First of a11 D．After all
Sun Yang, a young Chinese swimming talent, several gold medals before the 2012 London Olympics.
A．won B．has won C．had won D．were to win
In hot summer, milk quickly turns sour it is refrigerated.
A．while B．if C．until D．unless
He found himself by a crowd of excited people and to escape.
A．surrounded; trying B．surrounding; trying
C．surrounding; tried D．surrounded; tried
