insure against something
phrasal verb with insure verb uk/ɪnˈʃɔːr/ us/ɪnˈʃʊr/
对…采取预防措施
to do something in order to prevent something unpleasant from happening or from affecting you
We thought we'd insure against rain by putting a tent up where people could take shelter. 我们想为了以防万一得支起一个防雨帐篷，这样大家就可躲雨了。