Question

1. Warn sb.... (a person or thing which is bad, dangerous, unusual, etc.
I had been warned...... Jim.
She warned me..... the traffic.

2. Warn sb..... (a danger sth bad which might happen later)
Scientists have warned us..... the effects of a global warming.

Accepted Answer

1. About 2. About / Of

Front	1. Warn sb.... (a person or thing which is bad, dangerous, unusual, etc. I had been warned...... Jim. She warned me..... the traffic. 2. Warn sb..... (a danger sth bad which might happen later) Scientists have warned us..... the effects of a global warming.
Back	1. About 2. About / Of

Warn Warned Sb Person Thing Bad Dangerous Unusual