UNIT 18 B1 - INVENTIONS & DISCOVERIES

I can't remember the ______ year it was discovered, but it was around 1975.

• complicated

• sudden

• exact

• unique

Was it a/an _____ decision, or had you thought about it for a long time?

• sudden

• automatic

• exact

• complicated

Do you know who _______ the planet Mars?

• invented

• discovered

• ran

• operated

You need four people to _______ this machine.

• invent

• discover

• estimate

• operate

Each person's fingerprints are ______. No 2 people have the same fingerprints.

• sudden

• artificial

• complicated

• unique

There is a ____ of phone in this office. We need some more!

• lack

• effect

• kind

• type

My computer has _______ ______ again.

• found out

• broken down

• pulled off

• come across

Jenny was late for chemistry so she _____ ____ a story about being attacked by a dog!

• found out

• threw away

• made up

• came across

I wonder when time machine will be invented in the ______.

• opinion

• future

• end

• last

What is the _________ between H₂O and H₂SO₄ ?

• different

• difficult

• difference

• difficulty