Complex sentence: In 2004, he became the Honorary Secretary of the Hong Kong International Film Festival Society Ltd. and a member of the Executive Committee of the Hong Kong Philharmonic Society Ltd. He resigned all these posts when he assumed office as the Chief Secretary for Administration.
Split into simpler sentences: In 2004, he became the Honorary Secretary of the Hong Kong International Film Festival Society Limited and a member of the Executive Committee of the Hong Kong Philharmonic Society Limited. However, he resigned all the posts when he assumed office as the Chief Secretary for Administration.