1． This book was so well worth __________ (read) that I bought it without hesitation.
[答案] reading
2．Some students even have no idea of why they are studying, so they are __________ (aim) most of the time.
[答案] aimless
3．The children talked so loudly at dining table that I had to struggle __________ (hear)．
[答案] to be heard
4．Instead of focusing __________ your wounded feelings, learn to look for the love, beauty and kindness around you.
[答案] on
5．The project has been a great success and I would like to thank all the people __________ (involve)．
[答案] involved
6．Habitat loss and climate change will be the biggest reasons for their __________ (extinct)．
[答案] extinction
7． It can make people more __________ (energy)．
[答案] energetic
