Line AD is called a ...... line.

The ...... produces more than 500 cars a day.

...... increased by 20% after they installed air conditioning.

Scientists have ...... a new type of motor which runs on ethanol.

Biologists have been ...... with bacteria which will eat plastic.

The cars are ...... at a factory outside Beijing.

The ...... of the puzzle is to make each side of the cube the same colour.

The paintings are on display at a/an ......... which opened on Friday.

I couldn't afford an expensive computer, ......... I bought a cheaper one.

Several of the components, ......... the microchips, are produced in Japan.

At first, air conditioners were not installed in private homes ......... they were too large and expensive.

The heat made employees uncomfortable, ......... employers decided to install air conditioning.

James is particularly keen ......... football.

Employees' output increased ......... their working conditions improved.

Domestic appliances have improved the way people live. ........., washing machines save people several hours of hard work each week.

The exhibition has been open ......... last week.

I haven't spoken to her ......... we were in high school.

He studied at Cambridge University ......... five years.

I've been waiting ......... ages.