Natural resources are things that we use that come from Earth.  Out natural resources are limited（有限的）.  This means that they will not        forever.  Some are renewable, like when you plant a new tree when you       one down.  Others are not renewable, like when you dig coal（煤）out of the       . Once it is used, it is gone.People realize the       that Earth’s natural resources are limited, and can do things to help conserve（节约）those resources.        you try to conserve a natural resource, you try to use less of it, so it does not get used up so      . One way that people conserve fuel, like gasoline, is by riding a bicycle or walking when the       is short instead of driving everywhere.Water is a very important natural resource because we all need it to stay       . We can conserve water       making sure that our pipes and taps do not leak（漏）.  We can also make        choices to conserve water, like only using the dishwasher or washing machine when theyare full.  Everyone can make contributions to protecting natural resources.

A．last B．spread C．burn D．change

A．turn B．cut C．put D．move

A．station B．building C．ground D．brick

A．news B．plan C．decision D．fact

A．When B．Although C．Whatever D．Whether

A．slowly B．hard C．regularly D．fast

A．money B．space C．place D．distance

A．alive B．alone C．asleep D．awake

A．about B．for C．by D．with

A．generous B．funny C．wise D．surprising