As versus Like

As and like are both translated to como in Spanish, but their usage in English is distinct, so they are often confused. Basically, as is used for fuctions and like for comparisons and examples. For example:

I work as a secretary. (function – I ama a secretary.)

I work like a secretary. (comparison – I am not a secretary but I do similar tasks)

I have done office jobs, like secretary or administrator. (examples)

I have done office jobs, such as secretary or administrator. (such as means the same as like in examples)

We often use like after the sensory verbs to make comparisons:

He looks like he's drunk. (judging by his appearance)

He sounds like he's drunk. (judging by his voice)

I feel like I got run over by a car. (a sensation I have)

We can also substitute like for as if or as though to make comparisons:

I feel as if I got run over by a car. 

I feel as though I got run over by a car.

Also, we use as.. as to mean tanto… como (and its opposite: not as... as), and the same as to mean igual que. We always separate as... as with an adjective or an adverb, while  the same as is not always separated by an object.

She’s as heavy as you.

She’s not as heavy as you.

She’s the same weight as you.

She weighs the same as you.

And finally, we use as usual to mean like always:

It's business as usual!