,1.“主将从现”的“现”就一定是一般现在时吗？可否是现在完成时或其他现在时态？2.您上次在课里讲到，若句中出现了影响就不用完成时，那么为什么这个句子I wish I havennot give up so easily,but now it is too late--I have already lost such a good chance.在这句中有提到影响，为何主句依旧用现在完成时？3.在""Ladies and gentlemen,please fasten your seat belts.The plane is taking off.""一句中，用进行时表将来。那么我是否可以将is taking off换成""will take off""?若不能，请解释理由。谢谢解答

,I wish I havennot give up so easily,but now it is too late--I have already lost such a good chance.这是个虚拟语气。听虚拟一课Ladies and gentlemen,please fasten your seat belts.The plane is taking off.""is taking off换成is going to take off 意思更接近一点