1 . He always participated to the best of his ability in whatever they were doing. That was___________ none of the children thought it unusual that David had decided to join the cross-country team. (用适当的词填空)

2 . I wanted to be sure everything was perfect. That is ____I double-checked the address on the electronic order. (用适当的词填空)

3 . Bill Cunningham was an observer, and not one of the observed, a worker not a star——and this was _______ he wanted it. (用适当的词填空)

4 . The syrup(糖浆) finally turned into a solid coating, like the crystal on the surface of haws. That is ________ they are also called bingtanghulu. (用适当的词填空)

5 . The area was hit by severe floods. That’s ____so many volunteers went there during a few days. (用适当的词填空)

6 . A shark that walks in water instead of swimming might sound like a creature straight out of a science fiction film. However, that is exactly _________ four new species of sharks move across the seafloor. (用适当的词填空)

7 . We endeavor to pursue our dreams by working.That’s ________ we don’t work only for a salary. （用适当的词填空）

8 . That’s ________I have a membership at the coworking space across the street—so I can focus. (用适当的词填空)

9 . Actually, girls can be ________ they want to be just like boys, _________ it is a pilot, an astronaut, or a manager . （用适当的词填空）

10 . College is________ you meet your bridesmaids, groomsmen, neighbors, and potential bosses. （用适当的词填空）