ADJ
- important, significant
- big, enormous, great, huge, major, strong, substantial
- minor, modest, small
- invaluable, positive, useful, valuable
- We like to think that we are making a positive contribution to society
- notable, outstanding
VERB + CONTRIBUTION
- make
- He made a major contribution to peace in the region
PREP
- ~ to
- a valuable contribution to science
ADJ
- generous, large
- small
- voluntary
- We rely entirely on voluntary contributions
PREP
- ~ to/towards
- I'd like to make a small contribution to the cost of the holiday