不定时作定语,表明这个动作尚未发生.
如,I'll find something to eat.(to eat要吃,但是还没有吃)
Sorry,I can't go with you.I've several letters to write.(to write要写,尚未写)
现在分词定语,说明这个动作正在发生.
People wishing to see the Great Wall know something about China.
(wishing表明正在盼望着)
The girl sitting by the door is my sister.(sitting正在坐着)