根据句意及首字母提示完成单词① Paper can be r{#blank#}1{#/blank#}. We'd better not throw it away.
② It is important to try to save e{#blank#}2{#/blank#}.
③If we don't protect our e{#blank#}3{#/blank#}, the earth will be destroyed.
④ Our teacher tells us to collect r{#blank#}4{#/blank#} plastic bags.
⑤ Gold, silver and iron are all m{#blank#}5{#/blank#}.
