As … As Comparisons: Saying Two Things Are Equal

The as … as structure says two things are equal, where a comparative says one exceeds the other. She is as tall as her brother claims they match; she is taller than her brother does not.

The pattern is fixed: as + plain adjective + as + the thing compared. The adjective stays in its positive form and never takes -er – as taller as is impossible.

• This copy is as good as the original.
• The second attempt was as expensive as the first.
• Nothing is as frustrating as a silent error.

The negative: not as, not so

To say two things do not match, negate the verb. Both not as … as and not so … as are correct, with not so sounding more formal and now much less common.

• The sequel is not as good as the original.
• The sequel is not so good as the original.

Both mean the sequel is worse. Note that this is a gentler way of saying it than the sequel is worse, which is one reason the structure is useful in writing that needs to criticise carefully.

Adding a measure

A quantity can sit in front of the first as to say by how much the two match or fail to:

• twice as long as, half as heavy as, three times as expensive as
• nearly as fast as, almost as good as, just as difficult as

One caution: twice as cheap is ambiguous and worth avoiding – half the price is clearer and cannot be misread.

As tall as he, or as tall as him?

Strictly, as is a conjunction introducing a clause whose verb has been left out, so the pronoun takes the subject form: she is as tall as he (is). In everyday English the object form has taken over completely: as tall as him.

Both survive. The subject form sounds formal and occasionally stiff; the object form is standard in speech and in most writing. Where the choice could cause confusion, restore the missing verb – she likes him as much as I do says something different from she likes him as much as me, and spelling out the verb removes the ambiguity entirely.

Fixed expressions

English has a large stock of frozen as … as similes: as cold as ice, as light as a feather, as stubborn as a mule, as clear as day. They are comparisons in form, but they function as single units of meaning, which is why swapping the noun rarely works – as light as a leaf is grammatical and sounds wrong.

Practice

Rewrite each comparison using as … as. Answers below.

1. The second draft was better than the first. (make them equal)
2. This bag is heavier than that one. (make them equal)
3. The sequel is worse than the original. (use the negative form)
4. The new route takes half the time of the old one.
5. Nothing frustrates me more than a silent error.

Answers

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