They are wating reource, for example, time, energy and money.
上面这句话不错，只是转折词for example不妥当;应该这样：
They are wating reource. For example, they ue too much time, energy and money.
不然就要换一换转折词，改用uch a或like：
They are wating reource, uch a time, energy and money.
不管任何语言，转折词(tranitional word)都扮演着一个重要角色，就是：承先启后，使句子紧凑，段落相吸，对文章结构，有良性作用。但是有些人几乎没有采用转折词的习惯，结果文句松散，上下文七零八乱，应该避免。
现在把主要转折词，分类列下，供大家参考。
Ⅰ表示尤有进者的意思：
Again, alo, then, beide, further, furthermore, moreover, next, in addition等，如：
① Jaon teache diligently. Beide, he write a lot.
② Englih i a ueful language. For one thing, it i an official language in the UN. Then, it i widely ued in buine, cience and technology.
Ⅱ表示反意见：
But, however, till, yet, after all, for all that, in pite of, on the contrary, on the other hand等，如：
③ Jim i intelligent but lazy.
④ Singapore i not a big country.On the contrary, it i very mall.