Did it happen by accident or by design?

I know her by sight but not by name.

We met by accident.

She hit me by accident.

The prices increased by 10%.

May I sit by you?

They parted by mutual consent.

We crossed France by train.

I stick by my promise.

He will come by plane.

She was overwhelmed by panic.

They are related by marriage.

They will arrive by plane.

The days slowly crawled by.

Sales dropped by 17 percent.