一 Have you figured out how much the trip will cost?—$4,000, or   like that.

A smile costs _______, but gives much.

 We feel________our duty to make our country a better place.

---So can I ask you a few personal questions?---No problem. I like ________ when people are open and direct.

 The biggest cities in Canada only have about six million people while _______ in China are much larger.