The phrase 'raise the morale' is correct and usable in written English.
You can use this phrase typically when referring to improving the energy, optimism, and enthusiasm of a group of people. For example, "The manager made an effort to raise the morale in the office by organizing team-building activities and introducing new motivation strategies."
"He visited the F.B.I. and the C.I.A. on Christmas Day 1999 to raise the morale of exhausted officials".
"Those are miserable attempts to raise the morale of terrorists who are fleeing our valiant armed forces," said SANA, the official news agency.
No doubt, but his words are hardly likely to raise the morale of the foot-soldiers of the Sri Lankan army holed up in the Jaffna peninsula.
At the station house, Mr. Bloomberg sought to raise the morale of the officers who work there now, praising their work in fighting crime.
"They are trying to raise the morale of their fighters and supporters, and show that they still have strength and can strike out elsewhere".
He said that teachers were preparing a curriculum that would include instruction on a new constitution, the fall of the previous government and lessons designed to "raise the morale of students".
During the siege of Saragossa, which began in 1808, a miraculous apparition of a palm tree with a crown raised the morale of the entire population.
Raising the morale of the militiamen, loyalists of the cleric, Moktada al-Sadr, have spread their insurrection across central and southern Iraq, the country's Shiite heartland.
The following year he became a research officer at the army's Bureau of Current Affairs, a body charged with educating and raising the morale of returning servicemen.
"I never use mortars – they are good for raising the morale of the troops, but you risk injuring civilians," said Major Steele.
"They worked in 24-hour shifts and they cleared that mail out and were credited with raising the morale of the troops.
