31 On a clear night．people can see5 P. U, @2 H3 v, \( t, [, y
A 150 stars& g& \7 C" T" ]7 F: L. Z# y, B
B hundreds of stars
0 \" E5 j! M+ s& s1 S+ g, VC one thousand stars
1 o$ `% H% f( x) R. A9 j4 q: ?, ID more than 14,000 stars
% W+ O% J7 ^( _% \; X! \( R _32 Light pollution occurs when# w8 e9 I! X- X' U5 B
A artificial lights illuminate the night sky
, L: ^) \5 O% t6 d3 q1 AB the moon lights up the night sky" W( e6 N+ D- l) ]9 H* G
C too many stars are visible in the night sky．% Q5 c# g; ` r N8 e0 {2 y
D streetlights are turned off: z& G! |$ x& H9 C0 Z" F* d
33 Nowadays even suburbs are becoming unsuitable for scientists to do their jobs
" O5 {, f# u7 j: tbecause
, C1 z% a6 `, p: }A the night sky there is too dark
+ l& @" E0 g0 q' V* f" N$ r! y1 s% q' NB the once dark areas are also polluted by fights．( _4 T+ x/ n" D3 h- b3 p( l( }, q ^
C these areas are not polluted by chemicals
& X- d1 r- m A h! u8 s3 nD these areas are less developed$ f; t$ x8 r) E' d3 T' ?
34 How does light pollution affect wildlife?
) z$ U0 M2 w1 D- `' Q! o2 ?0 HA Animals may go off course1 u' P5 D' y& o8 K9 m1 D
B It helps migrating birds find their homes
0 ~0 H1 b( m$ h& L4 xC Animals are afraid to go out after sunset. y% @4 @7 ], h7 h0 b0 l
D It helps birds fall asleep
; ?, ?) ^% N7 { q1 V1 B35 The title“Light Night，Dark Stars”means
# M6 \3 V+ W5 EA the night sky is brightly lit up and stars are black
* T/ n: `, S( j& V5 d- hB lights appear at night and stars are seen in the dark0 m: h4 L4 l) J& C
C city lights at night illuminate stars in the sky9 f% B {) C5 E. s; {' M
D city lights illuminate the night sky．making stars invisible |
发表于 2012-8-16 00:07:50
