This process is thought to occur by one of two processes.

EM is thought to occur in about 80% of infected patients.

This process is thought to occur very rarely in evolution for two major reasons.

The material had not been thought to occur in freshwater plants.

"It was previously thought to only occur in the developing brain," he said.

In the developing immune system, however, the opposite has been thought to occur.

The sugar was previously not thought to occur in nature at all.

He also said the problem was thought to occur in cold weather.

Infection was originally thought only to occur through the air.

His election as president was thought to occur under the pressure from the Syrians.