Glass bottles were first made about three thousand years ago. The oldest bottles were made (6) hand. People blew them into different shapes by using long iron tubes. People blew through the tubes. The tubes left a mark on the finished glass,(7) this mark shows that the glass was blown.There are other ways to tell if a bottle was hand-made. The glass might have bubbles in it. The bubbles probably came from boiling the glass. Usually the bubbles would stay in the glass as they (8) .
Then people began making bottles other ways. For example, they poured the glass into forms. It took two forms (9) a bottle. There was one form for (10) half. By putting these two halves together you get a bottle. Bottles (11) this way have lines down the sides. That’s (12) the two halves were joined together.
A (11) (A) made (B) making (C) who are made (D) which made
D (12) (A) the place (B) which (C) what (D) where