I want to hear from her again, , we have been out of touch for more than thirty years.
| A.What's more | 
| B.That is to say | 
| C.In other words | 
| D.Believe it or not | 
Scientists think they have _____ in their attempt to find the causes of some major dieases.
| A.broken through | B.worked out | 
| C.fallen out | D.got round | 
If you ever have the _____ to go abroad to work, you should take it.
| A.possibility | B.offer | C.luck | D.chance | 
In aerospace devices the weight of the necessary power producing equipment is _____.
| A.vital | B.possible | C.capable | D.reliable | 
Stressful environments lead to unhealthy behaviors such as poor eating habits, which _____ increase the risk of heart disease.
| A.in turn | B.in return | C.by chance | D.by turns | 
The family is a cooperative enterprise for which it is difficult to _____ rules, because each family needs to work out its own ways to deal with its own problems.
| A.set up | B.put down | C.keep up | D.lay down |