Common Mistakes : Except

preposition

.BAD: Except smoke and traffic fumes, there are several other types of pollution
.GOOD: Besides smoke and traffic fumes, there are several other types of pollution

: except = not including; but not
.She eats everything except fish

: besides = in addition to
.Besides football, he also plays tennis and badminton

.BAD: The old lady never spoke to anyone except someone came to visit her
.GOOD: The old lady never spoke to anyone unless someone came to visit her
.GOOD: The old lady never spoke to anyone except when someone came to visit her

Except (a preposition) cannot be followed by a clause that has a finite verb (‘came’). Use unless (a conjunction) or except when, except while, except if, except that
.Americans are just like any other people in the world, except that they are more tolerant
.He tends to ignore me except when he needs something

.BAD: I had never really spoken to him except saying hello
.GOOD: I had never really spoken to him except to say hello

: When you are talking about purpose, use except + to-v
.I rarely go the market, except to buy vegetables

.BAD: They want nothing except seeing that the children are happy
.GOOD: They want nothing except to see that the children are happy

.BAD: My brother is good at everything except to wash the dishes
.GOOD: My brother is good at everything except washing the dishes

The choice of verb form after except is sometimes determined by a word that comes earlier in the sentence, e.g. want + to-v, good at + v-ing

.BAD: In their free time they do nothing except going from one cafeteria to another
.GOOD: In their free time they do nothing except go from one cafeteria to another

.BAD: She was willing to do anything except to tell me her name
.GOOD: She was willing to do anything except tell me her name

: do (anything/nothing/what you like etc) + except + bare infinitive
.There was nothing I could do except sit and wait