小题1:It is our d________ (责任，义务) to try to cut back on production and reduce the amount of things we make and buy.
小题2:Trees a________ (吸收) the carbon dioxide in the air to produce oxygen.
小题3:People have harmed nature through a________ (农业), fishing, hunting and tourism.
小题4:Many countries have hesitated to give p________ (准许，许可) for the production of GM foods, as they would rather be cautious with this new technology.
小题5:I feel really g________ (内疚的) because I made some cruel remarks too.
