(1)结构上的变化
例：This seems mostly effectively done by supporting a certain amount of research not related to immediate goals but of possible consequence in the future.
给某些与当前目标无关但将来可能产生影响的科研以支持，看来通常能有效地解决这个问题。
(2)用词上的变化
例：Interest in historical methods has arisen less through external challenge to the validity of history as an intellectual discipline and more from internal quarrels among historians themselves.
人们之所以关注历史研究的方法论，主要是因为史学界内部意见不一，其次是因为外界并不认为历史是一门学问。
例：The behavioral sciences have been slow to change partly because the explanatory items often seem to be directly observed and partly because other kinds of explanations have been hard to find.
行为科学之所以发展一直缓慢，部分原因是用来解释行为的依据似乎往往是直接观察到的，部分原因是其他的解释方式一直难以找到。
