We can use like or as to say that things are similar.

• She is like her sister.
• He is a doctor like his father.
• Like his brother, he is a vegetarian.
• You are dressed just like me.
• He fought like a tiger.

Grammar notes

Like is a preposition. It is used before a noun or a pronoun which acts as its object.

Using as

As is a conjunction. It is used before a clause or an expression beginning with a preposition.

• Nobody loves her as I do. (NOT Nobody loves her like I do.)
• In 1939, as in 1914, everybody seemed to want war.
• He fought as a tiger does.

Informal use of like

In informal English like is often used a conjunction instead of as. This is very common in American English.

• Nobody loves her like I do.

Comparison with as and like after negatives

Note the word order in the following sentences.

• I don’t sing, like Jane. (Jane sings, but I don’t.)
• Like Jane, I don’t sing. (Jane doesn’t sing; neither do I.)
• I am not a Catholic, like Mary. (Mary is a Catholic, but I am not.)
• Like Mary, I am not a Catholic. (Mary is not a Catholic; nor am I.)

These sentence connectors are used to emphasize the fact that the second point contradicts with the first.

HOWEVER : Katty couldn't cash her paycheck However, she managed to buy a new TV set.

BUT: Oscar had a ticket, but he didn´t go to the game

NEVERTHELESS: There was little chance of success; nevertheless they decided to perform the surgery. STILL He is rich. Still, he leads a miserable life.

YET: Edison dropped out school at an early age, yet he became a famous inventor

WHEREAS. Tom thinks we´re ready to begin whereas Lisa thinks we have to wait