刺激

Interest is an incitement to study.

Light stimulates plant growth. / Light is a stimulus to growth in plants.

powerful/strong stimulus/incentive

economic incentive

mechanical irritation

enviromental/external stimulus

sensory/erotic/sexual stimulation

stimulant measures

be susceptible to stimulation

receive stimulations (from); receive a fillip/stimulus

promote/stimulate demand (for)

stimulate consumption and economic growth

whet/stimulate/quicken/sharpen one's appetite

excite a nerve

stimulate/spur economic growth

stimulate export/trade/production

She was badly upset by the sad news.

She has a weak heart, and should avoid excitement.

Don't provoke him.