Common Mistakes : By

preposition

.BAD: He managed to open the lid by a screwdriver
.GOOD: He managed to open the lid with a screwdriver

:(You do something with a tool, instrument, etc (NOT by
.He opened the envelope with a chopstick
.You can’t eat spaghetti with a spoon

.BAD: I am staying in a small town by Oxford
.GOOD: I am staying in a small town near Oxford

:by = next to or very close to something
.I’ve been sitting by the phone all morning waiting for her to ring
.I’ll meet you on the corner, by the bank

:When talking about the position of towns, cities, countries etc, use near
.I spent the first month in a little village called Farchant, near Garmen-Partenkirchen

.BAD: We can gain a lot of knowledge by these books
.GOOD: We can gain a lot of knowledge from these books

:You get information from a source
.You can learn a great deal from a good dictionary
.I obtained their new number from directory enquiries

.BAD: Being locked up is a punishment by itself
.GOOD: Being locked up is a punishment in itself
.BAD: Money by itself is of no interest to me
.GOOD: Money in itself is of no interest to me

:in itself = without anything added
.His offer to pay for the repairs is in itself an admission of guilt