We wish to notify you that Mr. Robert Smart, who has been our representative in Southwest England for the past seven years has left our service and therefore no longer has authority to take orders or collect accounts on our behalf. We have appointed Mr. Fred Peterson in his place.

A．If clouds are high, there will be bad weather.
B．The color of clouds is a factor to help predict the weather.
C．If the weather is good, the clouds must be very low.
D．To study clouds is the only way to understand the weather.