She has to _______ her journey because of her mother’s illness.

He didn’t selfishly keep for himself the money inherited from his uncle. Instead, he made a ______ contribution to help the community.

After the mass shootings at Sandy Hook Elementary School, President Obama ordered his members to ________ solutions to gun violence.

(2013·浙江，4)As the world's population continues to grow，the ________ of food becomes more and more of a concern.

 It is high time that we started to consider what ________  we should take to reduce heavy smog caused by traffic fumes and other pollutions.