build forts on;strengthen against possible attack
make stronger,more effective,etc.
"This exercise will strengthen your upper body"
"strengthen the relations between the two countries"
"The U.S. is girding for a conflict in the Middle East"
"troops are building up on the Iraqi border"
"fortified milk"
"the punch is spiked!"
The..Bee..Employ'd at home..to fortify the Combs.
出自: Dryden