Page 183 - Perfect English Grammar: The Indispensable Guide to Excellent Writing and Speaking

future, and will for the other persons.

17.16 Spaces after a Period

The consensus among copyeditors throughout the English-speaking world is you
should use just one space after a period, question mark, or exclamation mark at

the end of sentence, as well as after a colon.

The main argument in favor of just one space is that modern computer
typography—which accounts for the vast majority of typed writing today—

automatically micro-adjusts the space after terminating punctuation so it is no
longer necessary to visually signal the end of a sentence with the broad expanse

of two spaces to go with a period that is not quite up to the job of doing it by
itself.

Most of the arguments in favor of two spaces amount to things like “it’s what

we have always done” or “that’s what my teacher told me in 1977.” If you are
still typing on a manual typewriter, then two spaces may make sense for you.

17.17 That versus Which

There is a subtle distinction between that and which that is largely followed only

in formal English in the United States, and is frequently not followed informally
in the United States or much at all in the United Kingdom. Knowing this

distinction can help add a bit of clarity to your writing; however, you may find
when this distinction is not observed, no harm is done.

Just as much confusion comes from not being certain where, or if, to place

commas as it does from not being certain whether to use that or which. Even
more confusion comes about because the two words are often interchangeable.

Generally, we use that with restrictive clauses and which with nonrestrictive
clauses. Restrictive clauses limit and provide details about the subject.

■ The house that is being built will belong to the mayor.