1 . The bell rang. Jacob smiled and he was glad his math class was _______. He grabbed his lunch bag out of his backpack and looked inside. He blinked. Beside his usual lunch, there was an envelope. Jacob opened it and slid out a (n) _______. It was of a suitcase. Jacob _______ what it meant.

The next day at lunchtime Jacob opened his bag. A new envelope peeked out. Inside was a tiny toy _______. Now he was _______! When he got home, he asked his mother, “Are we taking a plane somewhere?” She just _______ at him, her eyes sparkling. “I guess it’s a mystery(谜)” was the only _______ she gave him.

Over the next few days, Jacob _______ more: a small American flag, a leaf from a palm tree and _______ a juicy orange. Then one day, when he finally got to open his lunch bag, there was ________ in it except for his usual lunch. His heart sank. Maybe he had been wrong after all. Maybe there was no trip. He was very ________.

Just before the end of the day, the school secretary handed Jacob a small box. “This is for you and ________ your mother outside.” He opened the box. A smile slid across his face. He ________ and pulled out a small black hat with two round mouse ears.

He hurried down to the main school doors where his mother and father were waiting, with suitcases. “We’re going to Disney World, right?” Jacob couldn’t contain his excitement. “Mystery ________,” laughed his mother. “Come on, we’re headed to the ________!”

2 . Like many young people, Jessica wants to travel the globe. Unlike most of them, this 25-year-old is doing it _______ . She and her husband have spent the last two years traveling the world, stopping everywhere from Paris to Singapore. It might sound like one long, expensive _______ , but the couple has an unusual way to make their travel _______ .

They’re part of a new form of the _______ economy: an online group of house sitters. Throughout their no-cost stays in _______ homes, they feed pets and water plants in the homeowner’s _______ .

It’s not all sightseeing. The two travelers carefully _______ their trips, scheduling their days around the pets that are sometimes difficult to _______ . But house sitting also offers a level of _______ they can’t find in a hotel. “It’s like ________ at a friend’s house,” Jessica says.

The couple has a high ________ rate in getting accepted as house sitters and they always go beyond the homeowner’s ________ . For Jessica, that means ________ plenty of pictures of happy pets, keeping the house ________ and leaving a nice small gift before heading to the next house. “You want to make the homeowner feel that they made the right ________ ,” she says.