I can provide for you comfortably and I'll do my level best to be a good husband to you.
There's a breakdown gang doing its level best to get us clear.
But they were doing their level best to save the vessel: that was plain.
If you'll pay me ten dollars a week, Mr. Dart, I'll do my level best to earn it.
But you can be sure that I am bound to do my level best in anything I attempt.
"Now then, boys, I expect every one of you to do his level best," said Gif.
And they were really doing their level best to avoid such a punishment.
If he is a principal, then we'll do our level best to lay him by the heels.
We had all done our level best, but the waterfall had scored the most.
“Well, we can do our level best and try,” the other assured him.