問題詳情：
71. It is ___________ _(值得) to listen to the lecture.
72. People in China are l________ ____ a happy life.
73 she comes across new words in reading, she likes r___________ to the dictionary.
is thinking of __________ ___(擴展) his business.
e birds are rare and __________ ____(因此) we should protect them.
【回答】
hwhile ing rring nding efore
知識點：單詞
題型：單詞拼寫
