3. ask questions of 4 different types: 1) ask general questions to the sentences: a) drawing consists of pulling metal through a die. b) finally the edges are sheared off to give the final dimensions. c) the metal is stretched just beyond its yield point (2 to 4 percent strain) in order to retain the new shape. d) bending can be done by pressing between two dies. 2. ask alternative questions to the sentences: a) products may have a complex cross section. b) the most common rolled product is sheet. c) density is measured in kilograms per cubic metre. d) heat is lost by conduction through the base metal. 3. ask special questions to the sentences: a) resistance welding is widely employed in many fields of sheet metal or wire manufacturing . b) in 1896 hall in america and heroult in france discovered a molten solution capable of yielding aluminium under electrolyses. c) silica dissolved during the extraction process must be eliminated from the solution. d) the processes of welding can be divided into two main groups - pressure welding and heat welding. 4. ask disjunctive questions to the sentences: a) upsetting involves a flow of the metal back upon itself. b) such inclusions can be avoided by proper manufacturing procedures. c) welding processes are classified according to the sources of heat and pressure used. d) fusion welding is more effective with alternating current. 60
a) Does drawing consist of pulling metal through a die?
b) Are the edges sheared off to give the final dimensions?
c) Is the metal stretched just beyond its yield point (2 to 4 percent strain) in order to retain the new shape?
d) Can bending be done by pressing between two dies?
2. Alternative questions:
a) May products have a complex or simple cross section?
b) Is the most common rolled product sheet or strip?
c) Is density or viscosity measured in kilograms per cubic metre?
d) Is heat lost by conduction through the base or precious metal?
3. Special questions:
a) Where does resistance welding widely employed?
b) When did Hall in America and Heroult in France discover a molten solution capable of yielding aluminium under electrolyses?
c) What must be eliminated from the solution?
d) What groups can the processes of welding be divided into?
4. Disjunctive questions:
a) Upsetting involves a flow of the metal back upon itself, doesn't it?
b) Such inclusions can be avoided by proper manufacturing procedures, can't they?
c) Welding processes are classified according to the sources of heat and pressure used, aren't they?
d) Fusion welding is more effective with alternating current, isn't it?