To his great surprise John was elected chairman of Students’Union.A. a; a B. a; the c. t

问题补充：

To his great surprise, John was elected chairman of Students’Union.

A. a; a B. a; the c. the; the D. /; the

答案：

解析：冠词考查题。第一空chairman为头衔前面不用冠词；第二空普通名词专有化用定冠词。句意：令他惊讶的是约翰被选为学生会的主席。