11.   Those animals also provide a pool for scientific research and a sort of living gene bank to guard against extinction and to supplement fragmented wild populations.

12.   Floods have helped spread the disease by providing breeding pools for the mosquitoes that carry the virus.

v. + pool >>共 311
have 5.80%
play 5.58%
create 4.00%
shoot 3.69%
use 2.95%
increase 2.85%
expand 2.74%
leave 2.11%
fill 1.90%
win 1.69%
provide 1.26%
provide + n. >>共 996
detail 6.39%
information 4.94%
service 4.41%
support 2.30%
evidence 1.86%
assistance 1.63%
security 1.54%
money 1.50%
protection 1.39%
opportunity 1.33%
pool 0.03%
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