PDF chapter test TRY NOW

1. Machines are just equipment made by human beings to make their jobs __________.
   
 
2. It was especially during the __________ century, after the World wars, that most countries started using machines profusely.
    
 
3. Raw materials for the machines can be extracted from __________ which are deep underground passages.
   
 
4. The machines are cut and ___________ to fit.