(2013·浙江,7)________ how others react to the book you have just read creates an added pleasure.
44. —Look!The boy is doing some washing. —He is only eight years old, but he is very ________.
43. Learning a foreign language well takes a long time, ________?
42. Many countries are increasing their use of natural gas, wind and other forms of ________.
41. —Well, it's getting late. I must be going. Thank you again for inviting me to the party. —________
40. —Shall Tom go and play football? —Not ________ he has finished his homework.