[QUOTE=navi tasan;906557]1-He waited for me to sit before beginning to eat.
2-He waited for me to sit before he began to eat.
3-He waited for me to sit before he would begin to eat.
4-He waited for me to sit to eat.
They are all acceptable. #1 and #2 have effectively the same meaning. #3 has a different shade of meaning. #4 has practically the same meaning as #1 and #2, but is both clunky and potentially ambiguous.