“They are wasting resources, for example, time, energy and money.”
“They are wasting resources. For example, they use too much time, energy and money.”
“They are wasting resources, such as (or like) time, energy and money.”
Again, also, then, besides, further, furthermore, moreover, next, in addition等，如：
① Jason teaches diligently. Besides, he writes a lot.
② English is a useful language. For one thing, it is an official language in the UN. Then, it is widely used in business, science and technology.
But, however, still, yet, after all, for all that, in spite of, on the contrary, on the other hand等，如：
③ Jim is intelligent but lazy.
④ Singapore is not a big country.On the contrary, it is very small.
Therefore, so, hence, thus, accordingly, consequently, as a result 等，如：
⑤ Some people are over-ambitious. As a result, they are usually unhappy.
⑥ Tom did not work hard; hence, he failed.
Likewise, similarly, in a like manner 等，如：
⑦ You cannot writes without a pen. Likewise, you cannot cook without rice.
⑧ No one is allowed to speak Mandarin in an English class. Similarly, no one is allowed to speak English in a Mandarin class.
For example, in other words, for instance, that is 等，如：
⑨ There are some common errors in his composition. For instance, it is wrong to use "he" to replace "the queen".
To sum up, in brief, in short, on the whole, to conclude 等，如：
⑩ Some say Singapore is a nice place to live in. Others say it is not so nice. It is too competitive. In short, some like Singapore; some do not.