(2013·高考天津卷)If he had spent more time practising speaking English before，he________ able to speak it much better now.

 I really don't know how to thank you, but for your help, I ________ my lost necklace.

At a construction site in our city the workers have uncovered an ancient wall that_______ to keep the enemy out of the city, but it requires further evidence.

We would have called a taxi yesterday if Harold ________ us a ride home.

I’d rather that you ______ the operation right away.