</p> 练习: 1. Paragraphs 2 and 3 * L) y9 U5 ^" w& @' E, o, a
2. Paragraph 4
2 Z* _2 q( h x+ C4 z+ M 3. Paragraph 5 ! A; w8 I4 A2 u Q+ W1 P& p+ m) O
4. Paragraph 6
4 L; V. u" l" a- K* y; m8 t, A A Cloud-to-ground lightning occurring in the U.S. 7 ~, R, O! i$ T! m1 b
B Types of lightning
5 D- v& R( m( L, K) X+ x, { C Cause of lightning + `; y, e0 {% Z1 B2 i: @. A4 h+ s6 A
D Differences between thunder and thunderstorm
3 ~) Z2 s: }. C: g' y* g Y% O# c E Frequencies of thunderstorms occurring in the world and theU.S. 7 ~5 H$ d" z) c+ a' M" D
F Shock waves as thunder 9 b) x8 g. u5 J' {! Q
5. In most cases of cloud-to-ground lightning, the ground s surface …
" I) F5 D9 i0 S' w) @ 6. One form of lightning that … is ball lightning … 4 Z. V! n* {% }
7. Cloud lightning looks like a ribbon when its lighting channel … & a. I$ z/ o2 s; h+ u$ e! g
8. Although not fully understanding processes of lightning, man … , H0 P4 a& B7 y1 _
A occurs most infrequently. , Y m% Z, |: c% M$ Z
B is shifted sideways by strong winds.
2 R; U7 [! k1 k% P. A# Y; p( r C is often hidden from our view. S/ N% a7 d% \) \1 d
D is equipped with a good knowledge of various forms of lightning . ( l9 l3 r1 {$ G; i8 Q( {6 W, L2 Z6 t
E is estimated at 20 millions a year.
% p$ V { u- R3 C F is positively charged.
# C: C8 w S9 K4 N 参考答案:CBFE FABD |