Ⅰ.单句语法填空
1．It takes a lot of time and efforts to stop illegal trade in endangered(danger) animals.
2．Since you are interested in traditional Chinese culture，I think this festival is well worth experiencing(experience)．
3．When talking to a friend，we should be frank and without reserve.
4．If cancers are spotted(spot) early，there is a high chance of survival.
5．We turned around and found the girl struggling(struggle) in the lake，crying for help.
6．The boy sitting by the window seems to be reading(read) something interesting.
7．While visiting(visit) the park，I met a friend I once worked together with in Beijing.
8．You will live a rich life on condition that economy has improved.
9．Something must be done to protect the environment from being polluted(pollute)．
