The 20th century________ many new means of communication,like radios, televisions, telephones and the Internet.
Yang Liwei is regarded as our national hero, who is_________.
The number of people who______ English as a foreign language_______ more than 750 million.
——Is this the first time you _______ Qingdao?—— No, but the first time I _______ here, the city wasn’t so beautiful.
Watching TV is ______ a kind of relaxation, and it also_______ our knowledge.
The growing speed of a plant is influenced by a number of factors, _______ are beyond our control.