How to learn use of prepositions?

[Eduardo]

Test No. incompl/elem-1 "Speaking already", question 1

Can you hear what he is .........?

(a) saying
(b) speaking
(c) telling
(d) talking

Test No. incompl/elem-1 "Speaking already", answer 1

Can you hear what he is saying?

Correct answer: (a) saying
_________________________

Sometimes i don't know how to apply the preposition on properly in a sentence for example: I worked on this project for ten years or Explain me how to work on it. What to do???

[Torsten]

Hi Eduardo,

It's best to memorize the use of prepositions by learning word combinations such as at university, to go to school, to find out, to work for a company, etc.
In addition, you can purchase this excellent e-book covering most of the English prepositions and their use in various contexts:
http://www.english-test.net/download/7/index.html

TOEIC listening, talks: Returning a phone call