Mr. Smith is busy these days ________ a new book on how to develop a child’s reading skill.
#96734
A
working out
B
working on
C
working for
D
working with
推荐题目
Charles Babbage is generally considered to _______ the first computer.
#94390
A
to invent
B
inventing
C
to have invented
D
having invented
Don’t leave the water ________ while you brush your teeth. 
#94420
A
run
B
running
C
being run
D
to run
All things ___, the planned trip will have to be called off.
#97326
A
considered
B
be considered
C
considering
D
hating considered