2.After being sent to prison ,those teens regret no having taken advice
from their parents and friends.
若是 being sent 改成:have been sent可以嗎?
3.The coach ,together with his hockey team players.was warmly
welcomed when they got off the plane.
4.Mary put forward the proposal that program be postponed
until John came from abroad.
5.Only by eating less will you lose some weight.
請問若是把only 改成If or That 可以嗎?若不可以請告訴我原因