With a lot of difficult problems （）, the manager felt worried all the time.

单项选择题—I'm not too happy about the project．What shall we do next —（）．Everything will be OK in the end．

A．Don't worry
B．Anything as you like
C．I'm afraid not
D. I don't think too much

单项选择题European football is played in 80 countries, （）it the most popular sport in the world.

A. making
B. makes
C. made
D. to make

单项选择题—I wonder why Mr. Green looks quiet in class. —I'm not sure, but he （）a small accident driving here.

A. could have
B. might have
C. might have had
D. must have had

单项选择题I have been keeping the portrait．I can see it every day （）as it always reminds me of my childhood in Paris．

A．since
B．where
C．as
D．if

单项选择题终身教育思想形成于20世纪60年代的欧洲，由( )首先提出。