1. You ____________ fall asleep when you are driving.
2. You ____________ feed the cat, it isn't hungry.
3. ____________ you help me move the furniture?
4. A fish ___________ swim, but it ____________ fly.
5. The children ____________ leave school early tomorrow.
6. You ____________ wait any longer, you ____________ go now.
7. The fire spread quickly but everyone ____________ escape.
8. You ____________ drive so fast, we're not late.
9. ____________ we go climbing? - No, let's go swimming.
10. You can only smoke in the canteen, you __________smoke in this room.
11. You ____leave medicines in places where children can get hold of them.
12. My grandfather was very clever, he __________speak four languages.
13. I'm hungry. - Don't worry, I ____________ make a sandwich for you.
14. You ____________ shout, I can hear you.
15. She's got temperature, she ______go out today, she _______stay in bed.
Write the correct perfect modal for the following sentences. Sometimes negative forms are used
1. Nobody told her anything about the argument. She....................................... (know) about it.
2. We arrived too early. We....................................... (be) in such a hurry.
3. She................... (leave) the office because her coat and bag aren’t here.
4. I.........(drive) to work, but the weather was so nice that I decided to walk.
5. It’s possible that I....................... (forget) to tell Joe about the meeting.
6. You................. (call) her on her birthday. She never forgets to call you.
7. Your house looks great. You ………… spent a lot of time painting it.
8. Michael went running in the rain. He …………….. gotten sick.
9. It was so dark that I fell down the stairs. I ………… fixed the light.
10. Patty ……………. gone by bus. Why did she walk?
11. I called his apartment and nobody answered. He…………… gone out.
12. You …………. shovelled the front walk. It looks so clean.
13. He ……………… stolen the car. He was with me all the time.
14. My bicycle is broken. I never ………….. ridden it down the stairs.
15. Jim looks happy. I think he ………………. gotten a new job.
16. The chocolate cake is all gone! Someone …………. eaten it.
Problem-solving. Read the following text and find out the main nanotechnological innovations in medicine. Using your notes discuss with your partner the problem
How will nanotechnology revolutionize medicine?
Imagine a pump which is only a single molecule in size. It’s really hard. A team from Northwestern University did it earlier this year. In nature, molecules are constantly moving around in our bodies, transporting energy, oxygen, and even information from one place to another, this molecular pump is a rudimentary synthetic copy of something nature does all the time. This pump uses a dumbbell- shaped molecule, and a set of positively charged molecular rings. Sort of like two magnets repelling each other, the rings provide tiny amounts of energy that the synthetic molecule can use to make the pump ratchet at a predictable rate!
The problem with nanotechnology has always been powering itty-bitty things; and realizing they can harvest energy from nano-scalerings is enough is pretty huge or small. They’re hoping if they can improve the tech and capture MORE rings they’d have enough energy to power artificial muscles, or even whole nanomachines!
The development of nanotechnology has been steadily climbing over the last 40 years and with leaps like this, things are starting to get crazy. In 2004, scientists at New York University created a nanobot that bipedally “walks” on legs 10 nanometers long by adding a molecule called psoralen found in the seeds of celery, parsley, citrus fruits and the common fig.
A few years later, a study on the future of nanomaterials said we’re only 10 to 20 years from a nanosized factory. This psoralen molecule lets the nanobot “walk” along a DNA strand; the researchers envision this as the beginning of a nanobot conveyor belt for nanoassembly, think about the coolness of a nan0-sized car factory assembling nanobots for any imaginary purpose.
The NIH says nanocomputers and nanobots could revolutionize the medicine industry by creating nanobots which cold mechanically reverse plaque buildup in arteries, or prepare tissues for cryonic storage, repair spinal damage, rewrite individual bases in our DNA, improve the efficiency of our cells, or map the complicated connections of the mammalian brain.
In 1998, researchers (hypothetically) designed a red blood cell 200 times more efficient that our own. It was, in essence, an atomic – sized oxygen tank that could fill up in the lungs and distribute oxygen to the tissues way better than our own cells can.
If that sounds far fetched, take this for a spin.
Papers in the journal ACS Nano and Physics Today (among many others) from the last couple of years use what researchers are called “DNA origami” to carry medication directly to cancer cells. DNA origami is essentially a nano-engineered “barrel” that can carry drugs or information to a specific place, and release it!
Nanotechnology is getting better, better and better!
UNIT 7