问题补充：
Imagine how excited we were that our schoolmates had been admitted to some famous universities.
A. learning
B. having learned
C. to be learning
D. to learn
答案：
A. learning
B. having learned
C. to be learning
(答案→)D. to learn
解析：考查不定式的用法：句意：想象一下当我们听说同学被著名大学录取的时候我们有多么兴奋。这是感叹句，正常语序是：we were excited that our schoolmates had been admitted to some famous universities. 可知用be excited to do sth，这是不定式做原因状语的用法。选D。
