Question

1) in the last hundred years traveling (become) much easier and very comfortable. In the 19th century, it (take) two or three months to cross North America by covered wagon. The trip ( be) very rough and often dangerous. Things ( change) a great deal in the last hundred and fifty years.
2). Mark’s English ( improve, really ) isn’t it? He (watch) American television programs and (study) his grammar every day since he first arrived in San Diego

Answer 1

1)become ; used to take; used top be; have changed