He made up his mind to devote his life the river polluted.
A. to prevent; to be
B. to prevent; from being
C. to preventing; to be
D. to preventing; from being
网友回答
A. to prevent; to be
B. to prevent; from being
C. to preventing; to be
(答案→)D. to preventing; from being
解析：句意：为了过上幸福的生活，他下定决心一生致力于防止污染。第一空的to，用来构成固定搭配devote ... to ... 把……奉献给……此处to是介词。－－所以prevent要用ing形式，第二空to live 不定式作目的状语，注意：此处不是prevent... (from) doing sth 阻止……作某事。选D。