He did not regret saying what he did but felt that he _________ it differently. 

If you had told me in advance, I ________ him at the airport. 

It's dark, Mum ___ be waiting for my return.

— We would appreciate it if you could stay for lunch.— Sorry, I         . I have another appointment.  

You _______ pay too much attention to your reading skill, as it is so important.