课时作业(八) [必修模块3 Unit 8 Adventure]
[限时：30分钟]
Ⅰ.单项填空
1．It was ________ great shock to the world that two airplanes crashed into ________ World Trade Centre in New York on Sept. 11.
A．a；/ B．the；the C．a；the D．/；the
2．To keep healthy，Professor Johnson ________ cycling as a regular form of exercise after he retired.
A．took up B．caught on C．carried out D．made for
3．They ________the train until it disappeared in the distance.
A．saw B．watched
C．noticed D．observed
4．The main cause of the disease in China is drug abuse, ________is very serious in Yunnan.
A．what B．who C．that D．which
