Sentence:  to <WSD>commit</WSD> oneself to a certain action 
Meaning of the word marked with <WSD> tags:  To pledge or bind; to compromise, expose, or endanger by some decisive act or preliminary step. (Traditionally used only reflexively but now also without "oneself" etc.)<ref>http://muse.jhu.edu/journals/american_speech/v074/74.3shapiro.html</ref>