有读者问：不定式作定语用与分词作定语用有哪些主要区别？
首先让我们假定你所说的分词作定语乃指作后置定语用的分词而言。又为了将问题简化一些，让我们将分词仅限于现在分词来讨论。必须指出，在许多情况下，用作定语的不定式是无法与用作后置定语的现在分词进行比较的，因为它不能为相应的现在分词所替换，如：
(1)We have no time to lose .
(2)It's time to start .
(3)She has no patience to hear me to the end.
(4)That is not the way to settle such questions.
(5)I haven't got a ticket to see the temple?
(6)Who was the first to finish ?
(7)He has the ability to make a big plan.
反之，比如下列句中的现在分词也无法与相应的不定式互换：
(8)Oh, it's the cake burning .
(9)The book lying on the table is mine.
(10)There's little I could do for the time being .
(11)The man speaking to us the other day has gone to Japan.
(12)Houseplants requiring constant attention are not suitable for couples with little spare time.
(13)We admired the stars twinkling in the sky.
但在一定情况下，二者倒是可比较的。二者用作后置定语（不定式作定语时一般皆须后置）时的区别主要表现在时间与语义上。在时间上，不定式着重表未来，现在分词着重表“当时正在或经常”。在语义上，不定式着重表潜在可能与结果，现在分词着重表事实或真实情况。
现举几例比较如下：
(14)There is nothing to do . （to do 意味着“可做”）
(15)There is nothing doing . （doing 在此等于 being done, going on，意味着“正在被做”）
(16)There is a house to be built here. （to be built意味着“将要或计划要建造”）
(17)There is a house being built here. （being built意谓“现在正在建造”）
(18)Here is a leaflet to give full particulars of the plan. （to give 意味着会或可能提供）
(19)Here is a leaflet giving full particulars of the plan. （giving 在时间上表经常，意味着“事实上提供”）
(20)One firm to close down was Shenzhen Baomin United Company. （to close down 表结果）
(21)One firm closing down was Shenzhen Baomin United Company. （closing down 表“正在倒闭”）
有时，二者似乎无甚区别，如：
(22)The Tianjin company is the only one using （或 to use ）a complete imported production line, which is got from Italy.
最后，不妨提一下，用作定语的不定式往往有情态意义，如上述句（14）中的 to do 即有“可以做”或“值得做”的含义。
