By the skin of one's teeth

He has built a big business empire by his <u><em>sharp practices</em></u>.

To spill the beans

Why do you wish to <u><em>tread on the toes</em></u>?

To put one's hand to plough

He was undecided. He <u><em>let the grass grow under his feet</em></u>.

To be a good Samaritan

To hit the nail right on the head

To fight to the bitter end