As vs. Like

As and like can both be used to compare, but they are not used in the same way. Like is followed by a noun or a pronoun (a person or a thing). As is followed by a person + a verb, or it gives someone's role or job.

1. Like → similar to (+ noun or pronoun)

Use like to say that two things are similar. It is followed by a noun or a pronoun.

• She isn't a professional, but she sings like one.
• He looks like his father.
• It feels like summer.

Structure: like + noun/pronoun

2. As → role or function, or + person + verb

As has two main uses:

a) As = in the role of

• She works as a teacher. (= her job)
• He used the box as a table. (= its function)

b) As + person + verb

• As you know, the office is closed on Monday.
• Do it as I showed you.

Structure: as + subject + verb

3. Key difference

• He works like a machine. (comparison: he works very hard, without stopping)
• He works as a waiter. (role: it is his job)

4. Formal and informal English

In everyday speech, many people use like before a person + verb. In formal English, use as.

• Informal: Do it like I told you.
• ✅ Formal: Do it as I told you.