Prisci, my name is Andrew and I’m an American and a native speaker of English. If you would like to practice your English with me please let me know.

In comparisons, "like" only express similarity, whereas "as...as..." makes a more precise comparison that can even contrast degree or quantity. For example, consider A) The stones were hot like fire. (similar to fire) B) The stones were as hot as fire. (as much as fire) #A says that the heat of the stones was similar to a fire, more or less. #B says that the stones were at least as hot as fire. The imprecision of "like" often makes it the better choice in poetry: "her voice was soft like summer rain" in which "as" would ruin the image with its precision. There are situations where one word makes sense, but not the other. For example, "As far as I know, today is Wednesday" makes a comparison between what I know and the limits of my knowledge. It concisely states that what I know to be certain is limited by my knowledge, sort of a strange thing to say, but everyone intuitively grasps what it means. I cannot imagine a way of saying this using "like". It would require a whole paragraph.

I can't really answer you except to say I don't think there is any simple answer. A book on English grammar for non-native speakers would probably have 3 or 4 pages on "as" and "like".

Hi Prisci, Happy to help you with your English language.

As and like are both prepositions or conjunctions. The prepositions as and like have different meanings. As + noun means ‘in the role of’ , like + noun means ‘similar to’ or ‘in the same way as’. COMPARE: AS your father, I’ll help as much as I can. (The speaker is the listener’s father). LIKE your father, I’ll help you as much as I can. (The speaker is not the father but wishes to act in a similar way to the father). More: 1. We use like (but not as) to compare two things: Example: She’s got a headache like me. (Correct) She’s got a headache as me.(incorrect) 2. When we compare appearance or a behaviour, we use like, not as: Example: The house looks like a castle.(correct) That house looks as a castle. (incorrect) 3. AS is commonly used to talk about jobs: Example: He worked for a long time as teacher in Africa. (Correct) He worked for a long time like a teacher in Africa. (incorrect) 4. The conjunctions as and like have the same meaning when used in comparisons. Like is a little more informal. Example: Nobody understands him as I do. Nobody understands him like I do. From English Grammar Today. I hope this could help.