Which of the following sentences is correct?

Let's discuss _____ the ways of improving the basic skills of English.

One-third of the students _____ present in the class.

Each of the students who filled out the admission form ____ the test.

To discover is ______ about something that already exists, but to invent is ____ something new.

‘Well’ is usually an adverb and so describes ___ but when it refers to health it can be an adjective and describe _____.

Much as Rome ____ roads through Europe in the years of the Roman Empire, Britain _____ railways and strung telegraph wires in India.

We are moved not by the fall of ____ great man but the elevation to heroism of what we had taken to be ____ little man.