Define:
(a) hejira
(b) hajj
(c) caliph.

1.Muhammad's departure from Mecca to Medina in AD 622, prompted by the opposition of the merchants of Mecca and marking the consolidation of the first Muslim community.

2. the perglimage where muslims go to meca to visit the house of god the kebba.

3. the chief Muslim civil and religious ruler, regarded as the successor of Muhammad.

to contain the wave of communism

wait history, who want to talk about history, boring.