--- The fog is so thick that the express way ____ have been closed. --- You are right. I ____ have thought of that. Now we have to take another road.
The poor children are looking forward to _____ a Christmas present that day.
With so much work on hand, you ________ to see the game last night.
Perhaps I’m not quite fit for the job, but ________, please let me. have a try.
Happily for Johns mother, he is working harder to ______ his lost time.
Apple and Microsoft _______ with each other for the world market to sell more PC with their own free software.