Make sentences as in example. Use the correct form of the verbs.
  Equipment                       Function
1. demand valve      --->    control the flow of oxygen to the diver (for)
2. cylinders            --->     store oxygen under high pressure (used to)
3. contents gauge   --->     indicate the amount of oxygen in the cylinders (present simple)
4. cylinders            --->     transport oxygen with the diver (used for)
5. depth gauge       --->     indicate the depth of the water (designed to)
6. buoyancy jacket --->     support the diver in the water (for)
7. diving mask        --->     allow diver to see clearly under water (designed to)
8. contents gauge   --->     a kind of alarm clock for the diver (act as)
9. demand valve      --->     supply oxygen to the diver when he or she needs it (present                                                                                                                      simply) 
10. buoyancy jacket--->     a very strong lifejacket (act as)

Example: 1. The demand valve is for controlling the flow of oxygen to the diver.

2. Cylinders are used to store oxygen under high pressure3. Contents gauge indicates the amount of oxygen in the cylinders4. Cylinders are used for transporting oxygen with the diver5. Depth gauge was designed to indicate the depth of the water6. Buoyancy jacket is for supporting the diver in the water7. Diving mask was designed to see clearly under water8. Contents gauge acts as a kind of alarm clock for the diver9. Demand valve supplies oxygen to the diver when he or she needs it10. Buoyancy jacket acts as a very strong lifejacket