1. The word “it” (line 10) refers to
2. The word “they” (line 12) refers to
3. The word “they” (line 14) refers to
4. The word “these” (line 17) refers to
ll. understanding vocabulary
assembly
plants
vehicles
taken apart
fasteners
identify
vital
presented
vulcanized
hazard
a produced ,created
b remembered
c separated into pieces
d danger
e recognize
f the process of putting parts together
g made stronger by using a special chemical treatment
h machines that are used for carrying people or goods from one place to another
I trees
J things that are used to join parts of some thing together
K factories
L very important and necessary