I am also confused with the grammar rule.<br/>Which of the following sentneces are acceptable? <br/><br/>(1) His sister is five years younger than he, but she is taller than he.<br/><br/>(2) His sister is five years younger than him, but she is taller than him.<br/><br/>(3) His sister is five years younger than he is, but she is taller than he is.