The tree, which had no leaves, was a birch.
Which is used in nonrestrictive clauses, always set off by commas.
The tree was a birch. The fact that it was leafless is incidental.
The tree that had no leaves was a birch.
That is used in restrictive clauses, never set off by commas.
The birch tree under discussion is that one, the leafless one.
I understand these three words as I am reading; I just refuse to ever use them.
The first two refer to stating something with additional, unnecessary words. The last means to violate idiom, as in pleonasms and tautologies.
Strunk & White have Rule 17 as “Omit needless words.” Pleonasm, tautology, and solecism are three I shall omit.
There are amble temptations to use I, but these are spiritual temptations. Here, I refer to the temptation to incorrectly spell words by replacing an e with an i.
It’s liquefy and liquefaction,
rarefy and rarefaction,
and stupefy and stupefaction,
despite how correct the other spellings (with i instead of e) may look.
