Standard ............... when performing certain experiments in the laboratory have changed over the past twenty years.

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• Choose the correct answer in each sentence.

  The free clinic on Warren Street is ----------by volunteer doctors and nurses.

• Choose the correct answer in each sentence.

  A gate agent at the airport announced a flight  _____________  caused by severe weather at the destination.

• On weekends the Italian restaurant is often busy _____ hours of the day and night.

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• Do you mind if I watch TV late tonight?” “______________” 

• Choose the best answer: 
  Once upon __________ , there was a good king and his queen.

• Patients may hang their coats in the closet _____ the vending machine in the waiting room.

• There was nothing else he could do. That was_______ 

• Choose the correct answer in each sentence.

  Edward's Plumbing has six company- owned vehicles, two of  _________________  are now in the repair shop.

•                    he comes in half an hour, we shall go alone.

• Choose the correct answer in each sentence.

  Environmentalists were pleased with the community's ______________  in increasing recycling in the area.

• Everybody knows him, _______ know him. 

•  The boy insisted on ______________ a break after lunch. 

• ______ who knows______ about literature takes •Jeffrey Archer seriously as a novelist. 

• Choose the correct answer in each sentence.

  After hours of searching, the source of the water leak was _______________   identified by the plumber.

• When Tim was a child, there ............. a park near his house.

• Choose the correct answer in each sentence.

  The chef _______________   prepares the entree for a restaurant critic often comes out to greet him or her in person.

• Choose the correct answer in each sentence.

  The best method for improving the -------- of your home at little cost is giving the exterior a fresh coat of paint.

• 125.The government sends .................. teams of to check the quality of the tap water in both urban and rural counties.

• Choose the best answer:
  How can I ……….. you of her innocence?
   

• There was a lot of traffic but we managed .............  to the airport in time.