AS vs LIKE

I was confused about the usage of LIKE and AS, since we use them interchangeably in colloquial English. But, they cannot be used that way in GMAT. I used a couple mental notes to spot their differences, and correctness in sentences. Check them out, and I hope this helps.


LIKE

LIKE can strictly only be followed by an noun and pronoun.

When you are confused whether LIKE has been used correctly in a sentence, all you have to think about is what the sentence is actually saying. If the sentence says that one is similar to the other, you most probably will be safe with LIKE.

eg., LIKE Mary, I am intrigued. (Both of us are intrigued)

The same meaning can't be conveyed using AS. Check the following sentence:

AS Mary is intrigued, I am intrigued. (It would mean that I am intrigued because Mary is intrigued)

BUT, you need to avoid using LIKE when things are not strictly similar in essense.

eg., I love eating cold items, LIKE ice creams. (WRONG USAGE)( Seems like it means to say that I like both cold items and ice creams, as though both are entirely similar in essence: I like eating cold items, the same way as I like ice creams. It doesn't mean that one is a sub-category of the other.)

I love eating cold items, such AS ice creams. (RIGHT USAGE)


In cases that doesn't mean that the comparison is not completely similar, go with AS.

AS

AS can be a CONJUNCTION or a PREPOSITION.

Conjunction:
eg., AS a father is, so is his son.
2. AS I was strolling through the park, I saw a little sparrow.
3. AS you already know, I am not coming.

Preposition:
eg., AS your father, I care about you.
2. I care about you, AS I am your father.
3. AS a father, I should care about my son.