托福写作</p> integrated writing7 I3 C5 C" p, Y
说北美的corn受到rootworm的侵害,阅读想出了几个办法4 Z! |: M: r: d! G, R- P
1.用Pesticide% S* p9 H r6 z' a
2.早点种玉米(plant the corn earlier in the year), 这样等天气暖和后,corn的根就mature了,rootworm的Larvae就吃不成它的根了
3 z7 ~. H. g) i4 t2 ]9 \ 3.换着种(alternative),今年种玉米,明年种别的作物(crop),像有些farmer会corn和roy换着种,这样在种roy的时候,rootwarm的幼虫饿死后,就不会再去吃玉米了
, ]: f4 p( p$ g! q9 }# Q4 a4 o: A& | 托福听力7 R- i. W# x' R6 \% H, {$ x' O: _
professor反对说all methods have severe limitations
* Z+ |, S4 J0 g* d, B9 p- l 1.有些rootwarm对pesticide产生了resistance
. U. u, T. X% G1 C0 _" t 2.早点种的坏处是,corn会遇到frosts和snowstorms; k1 ^1 I, b- q( q
3.rootwarm已经adapt了这种换着种的方法,所以它们evolve出了一种egg,可以在土里买上几年在hatch,这样等它们hatch就可以吃到玉米根了
9 }3 H6 t4 {- w0 Z2 n independent writing0 D0 r1 C1 ?& s, [- h+ K
Do you think it is better for government to spend money on building furture housing or preserving historic or traditional buildings and homes?
9 E5 I( x6 P0 K 就只能回忆这么多了,请见谅!谢谢!希望对大家有帮助 |