--When _____ the abacus _____? -- In the sixth century by the Chinese people.
#44867
A
is, invented
B
did, invent
C
was, invented
D
does, invent
推荐题目
—Did the book provide the information you need? —Yes. But ________ it, I had to read the whole book.
#44812
A
found
B
to find
C
find
D
finding
Nobody ______ to go into the laboratory without permission (允许).
#44894
A
allows
B
is allowed
C
promises
D
is promised
Today Chinese by more and more people around the world.
#44664
A
speak
B
spoke
C
is spoken
D
was spoken