天然气不能有效缓解全球变暖 Both shale gas and conventional natural gas have a larger greenhouse gas footprint than do coal or oil, especially for the primary uses of residential and commercial heating. Dr. Robert Howarth, a professor of ecology and environmental biology, came to this conclusion after assessing the best available data and analyzing greenhouse gas footprints for both methane and carbon dioxide over a timescale of 20-years following emissions. The findings are published in Energy Science Engineering. While emissions of carbon dioxide are less from natural gas than from coal and oil, methane emissions are far greater. Methane is such a potent greenhouse gas that these emissions make natural gas a dangerous fuel from the standpoint of global warming over the next several decades, said Dr. Howarth. Society should wean ourselves from all fossil fuels and not rely on the myth that natural gas is an acceptable bridge fuel to a sustainable future.
“be+过去分词”与“get+过去分词”的区别
比较since和for
关于主动形式表示被动意义
延续动词与瞬间动词
何时使用被动语态
英语不用被动语态几种的情形
两类被动句型的转换
主动语态变被动语态的方法
be going to / will
主动形式表被动意义
现在进行时与一般现在时的区别
一般现在时代替过去时
一般现在时代替将来时
现在进行时
英语一共有多少种时态
现在进行时表将来有哪些特点
过去进行时与一般过去时的区别
英语主动表被动用法归纳
时态与时间状语
过去进行时
将来进行时
一般过去时的用法
不用进行时的动词
be to和be going to
if从句之后可接表示将来的be going to吗
since的四种用法
主动语态变为被动语态的方法
用现在进行时表示将来
“be said+不定式”的七种结构
将来进行时的“温和效应”
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