Complex sentence: Some went to Amman, where they found Amir Abdullah sympathetic to their cause, but under increasing pressure from the British, the young Abdullah drove them from Transjordan, where they rejoined other Syrian nationalists at Cairo In 1921, the Syrian-Palestinian Congress was founded.
Split into simpler sentences: Some went to Amman, where they found Amir Abdullah sympathetic to their cause; but under increasing pressure from the British, the young Abdullah drove them from Transjordan. These rejoined other Syrian nationalists at Cairo In 1921, when the Syrian-Palestinian Congress was founded.