.Although it had been______ struggle for him to finish the experiment, he enjoyed the result with________ satisfaction.
A good idea just ______ me — Let’s go swimming.
If I ruled the world, I would _______ the world ______ everything that is bad.
I will appreciate if you paid in cash.
It was not until dark he found he thought was the correct way to solve the problem.
The students are listening to the teacher with their eyes the blackboard.