增强

He is shy and needs building up his confidence.

The hurricane is gaining strength.

Promote physical culture and build up the people's health.

strengthen fighting capacity; increase combat effectiveness

build up one's confidence; heighten/strengthen/enhance/boost one's confidence

build up one's health; build up a strong constitution

revitalize/invigorate an enterprise

enhance the cohesion (of an organization)

enhance people's concept of democracy and legality

boost one's immune system

strengthen the economy

aid/enhance memory

enhance the vitality (of)

strengthen the power of a nation; increase national strength

raise/heighten/boost one's morale; strengthen one's militant resolve

enhance Party spirit