________ on ten years of observation and study, Professor Wang announced that everyone dreams every night,whether they realize it or not.
#88276
A
Basing
B
Based
C
Been based
D
Having based
推荐题目
Don't leave the water ____ while you brush your teeth.
#93088
A
run
B
running
C
being run
D
to run
 After describing the planned improvements, she went on _______ how much they would cost. 
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A
to explain
B
explaining
C
to be explaining
D
having explained
       by the advances in technology, many farmers have set up farms on their land.
#94658
A
Being encouraged
B
Encouraging
C
having encouraged
D
Encouraged