1 . I visited Hangzhou last summer, __________ is a beautiful city. (用适当的词填空)

2 . We are short of two people, without __________ we will need three more days to finish the work. (用适当的词填空)

3 . My classmates were friendly, with __________help I made great progress in my English learning. (用适当的词填空)

4 . Many lessons are now available online, from ___________students can choose for free. (用适当的词填空)

5 . ________ is known to all, Madame Curie won the Nobel Prize twice for her discoveries. (用适当的词填空)

6 . This year’s Nobel Prize for Physiology or Medicine has been awarded to Tu Youyou, ________ research led to the discovery of artemisinin. (用适当的词填空)

7 . I spoke to Dr. Smith just now,________ is always ready to help others. （用适当的词填空）

8 . Here are academic experts from America, some of ________are our old friends. （用适当的词填空）

9 . The number of smokers, _________ is reported, has dropped by 17 percent in just one year. （用适当的词填空）

10 . He passed the college entrance examinations, ________ made his parents very proud. （用适当的词填空）