I would like to know whether I can change the first sentence into the second and the third one.<br/><br/>Please check it out.<br/><br/>Thanks.<h2></h2><h2></h2><h2></h2>1. David works hard, as does my brother.<br/><br/>2. David works hard, which does my brother.<br/><br/>3. David works hard, and so does my borhther.