only to do 是only+不定式
可不定式的基本形式有好几种:to do to be done to have done to have been done
to be doing to have been doing
用不定式的那种形式,看不定式与主语的关系:主动 或 被动
例如:He hurried home only to find that his mother was in hospital. (主动)
He hurried home only to be told that his mother was in hospital.(被动)