We think that the smaller digestive system in Homo erectus was able to evolve because of the shift in diet,我們認為,正是食物的轉變使直立人的消化系統得以進化
able to能做 ...
I may be able to help you in some way.
我也許可以從某個方面去幫助你。
He was able to cast off such an uninteresting task.
他終于擺脫了這么一項乏味的工作。
because of因為; 由于
We win the game because of his participation.
由于他的參與,我們贏了比賽。
Because of his irresolute character, we were defeated at last.
因為他性格的軟弱,我們最終被打敗了。