The Metropolitan Transportation Authority on Monday unveiled an $18 million package of service improvements — the second time in two years that the authority has enhanced or restored service that had been cut in 2010 amid a budget shortfall.

The changes include more frequent G train service on weekdays from 3 to 9 p.m., an extension of the M train to the Delancey Street-Essex Street station in Manhattan on weekends, and the return of the B37 bus service in southwest Brooklyn.

Other improvements, like additional station cleaning and “better turnstile layouts” to improve the flow of foot traffic, are also planned.

“For the second year in a row, the state has invested in significant enhancements and expansions to our state’s transit system that will improve the experience of the eight million commuters who use the M.T.A.,” Gov. Andrew M. Cuomo said in a statement.