36. Doctors Without Borders dedicated themselves to _______ emergency medical services for the developing countries.
(A) provide
(B) providing
(C) provided
(D) have provided
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統計: A(64), B(75), C(4), D(2), E(0) #1781934
統計: A(64), B(75), C(4), D(2), E(0) #1781934