How do you say "She was generous with her time"?
She was generous with her time.


If you translate this phrase literally, it would be "對(花)時間她是慷慨的" (She was generous with her time). But we Chinese usually do not use the term '慷慨(generous) ' to describe the manner of spending time. We usually use  '慷慨' to describe the manner of disbursing money. 

Translate the phrase like this clearly shows it's a straight translation of an English sentence. In this instance, it is better to use the verb phrase '不計較(do not care) ' instead of the adjective '慷慨'


  她不計較花時間 (she did not care spending her time)


Depend on context, you can also interpret the phrase in different ways:

If she's always this way:


  "她對付出時間這一方面十分慷慨"
  
  (In regard of disbursing her time, she is very generous)


If you are referring how she acted in one instance:


  "她慷慨地付出她的時間"
  (She generously disbursed her time)
  
  "她不吝惜撥出自己的時間"
  (she was not stingy about allocating her time)