Complex sentence: With the support of the Middleton team and committee, Verity started bowling spin at the beginning of the 1929 season, and immediately began to attract more attention, culminating in an unsuccessful trial at Warwickshire.
Split into simpler sentences: With the support of the Middleton team and committee, Verity started bowling spin at the beginning of the 1929 season. Beginning to attract more attention, he had an unsuccessful trial at Warwickshire.