50. Finish the following statements according to the text.

1. Rock-fill dams have characteristics both ….

2. The rock-fill dam has two structural components ….

3. The embankment consists of ….

4. The impervious membrane is constructed of ….

5. The membrane is sometimes poured as a monolith without … but with …..

6. Rock-fill dams are subject to ….

7. The greatest disadvantage of rock-fill dams is ….

8. A rock-fill dam has high resistance to ….

9. Less material is required for … than for ….

10. Foundation requirements for rock-fill dams are more … than for earth dams.

11. Rock-fill dams are cheaper than concrete dams and can be constructed more rapidly if ….

51. Answer the following questions.

1. What are the two main structural components of the rock-fill dam?

2. What does the embankment usually consist of?

3. Should the rock be capable of resisting erosion and strong enough to withstand loads of high intensity even when wet?

4. Where can large stones of regular shape be used?

5. Why do most membranes have expansion joints at intervals of about 50 ft with asphaltic joint filler?

6. Where is slab thickness greater?

7. What may settlement result in?

8. What can leakage be controlled by?

9. Does a rock-fill dam of good design and careful construction have high or low resistance to earthquakes?

10. Why are foundation requirements for rock-fill dams more rigid than for earth dams?

11. Are rock-fill dams cheaper than concrete dams?

12. Can you name the most famous rock-fill dams in the world?

52. Read the text again, make a plan of it. Write down an abstract for text e.

53. Match the words with their synonyms.

1) characteristic	a) constructional
2) component	b) quick
3) structural	c) space
4) basic	d) feature
5) withstand	e) cope with
6) flat	f) occasional
7) ample	g) stiff
8) interval	h) element
9) instance	i) case
10) periodic	j) plentiful
11) rapid	k) even
12) rigid	l) fundamental

54. Match the words with their opposites.

1) loose	a) flexible
2) intense	b) tight
3) flat	c) bumpy
4) repair	d) wet
5) rapid	e) slow
6) dry	f) weak
7) regular	g) insufficient
8) ample	h) irregular
9) possibility	i) impossibility
10) rigid	j) brake

55. Using the dictionary add as many words as possible into the table.

Verb	Noun	Adjective
1.	characteristic
2.		structural
3.	base
4. to intensify
5.	settlement
6. to resist
7.		thick
8.	possibility
9. to withstand
10.	rapidity