—Must I turn off the gas after cooking ? --Of course . You can never be ___ careful with that.

There is ____ as a free dinner in this world, as the saying goes, “No pains, no gains.”

One of the greatest benefits of Internet friendships is that they are based on common interests, ________ appearance, age or popularity.

The doctor will see you again next week. ____, you must rest as much as possible.

In ancient times, people rarely travelled long distances and most farmers only travelled ___________ the local market.