* I try to make a better world by _______________.
1. recycling used materials.
2. building some senior centers after
I become wealthy.
3. inventing useful robots that can do
a good job for the world.
4. becoming the President of our
country.
5. making our country rich so that we
can help poor countries.
6. making good medicine to cure AIDS.
7. making good farming machines to
increase the effectiveness of
harvest.
8. becomeing a scholar so that I can
study my field and it will be
helpful to many problems in the
world.
(Would you check the expressions which would be suitable for the blank? Would you like to recommend better expressions?)
1 - 7 sound fine, except that "president" shouldn't have a capital P.
8 sounds OK, but check spelling (becoming) and make it more detailed (what are you studying? a type of engineering? or what?) -- also, some phrasing: ... so my knowledge and skills can be of help in solving some of the world's problems.