--When _____ the abacus _____? -- In the sixth century by the Chinese people.

--When _____ the abacus _____?   -- In the sixth century by the Chinese people.

#44867

is, invented

did, invent

was, invented

does, invent

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A new house ___ at the corner of the road.

#44460

is building

is being built

been built

be building

 This movie ________ on the Internet.

#44410

watch

watches

can watch

can be watched

---Please say“I’m here．”when your name _________.---Yes，Mr Smith．

#44669

be called

is called

is calling

calls

The dictionary mustn’t ________ from the library.

#44684

take away

taken away

are taken away

be taken away

Stamps are usually used _____letters.

#44752

to sending

to send

for send

for sent

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