Question

He reached the station _____ only _____ that the train had just left.

1. A.
   tired；learned
2. B.
   tiring；learning
3. C.
   to tire；to learn
4. D.
   tired；to learn

Answer 1

D
tired此处是过去分词，表示主语的状态。only to learn…此处的不定式表结果。