在自然状态下，某一桦树林中出现了云杉树苗，云杉长大后，高度超

【名词&注释】

主持人(host)、生物入侵(biological invasion)、生物进化(biological evolution)、呕心沥血、雪中送炭(provide timely help)、针砭时弊、天涯海角(ultima thule)、淋漓尽致(incisively and vividly)、秘而不宣(hush)

[单选题]在自然状态下，某一桦树林中出现了云杉树苗，云杉长大后，高度超过桦树林。桦树不如云杉耐阴，而逐渐减少，最终形成以云杉为主的树林，这种现象是

A. 初生演替
B. 生物入侵
C. 生物进化
D. 种间竟争

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学习资料：

[单选题]--My mother is preparing my favorite dishes, Go with me and have a taste, okay?--_______. And I’ll be glad to meet your parents.

A. I think so
B. I’d love to
C. I’m sure
D. I hope so

[单选题]下列词语中，字形和加点字的读音全部正确的一项是

A. 雪中送炭 笑容可鞠 戕害（qiāng） 针砭时弊（biān）
B. 呕心沥血 淋漓尽致^{(incisively and vividly)} 纤维（qiān） 汲取教训（jī）
C. 天涯海角^{(ultima thule)} 丢三落四 提防（dī） 道行很高（héng）
D. 朋比为肩 秘而不宣^(hush) 佛像（fó） 看家本领（kān）

[单选题]22 The workers——the glasses and marked on each box” This Side UP”

A. carried
B. delivered
C. pressed
D. packed

[单选题]41________

A. suggested
B. explained
C. announced
D. predicted

[单选题]BBoiler rooms are often dirty and steamy, but this one is el.ean and cool. Fox Point is a very new47-unit living building in South Bronx, one of the city’s poorest areas. Two-thirds of the people living there are formerly (以前) homeless people, whose rent is paid by the government. The rest are low-income families. The boiler room has special equipment, which produces energy for electricity and heat. It reuses heat that would otherwise be lost to the air, reducing carbon emissions(碳排放)while also cutting costs.

A. Fox Point is operated by Palladia, a group that specializes in providing housing and services to needy, people. Palladia received support from Enterprise Community Partners (ECP), which helps build affordable housing by providing support to housing developers.
B. ECP has created national standards for healthy, environmentally (环境方面) clever and affordable homes which are called, the Green Communities Standards. These standards include water keeping, energy saving and the use of environm entally friendly building materials. Meeting the standards increases housing construction costs by 2%, which is rapidly paid back by lower running costs. Even the positioning of a window to get most daylight can help save energy.
C. , whose duty is to develop and keep the city’s supply of affordable housing, will require all its new projects to follow ECP’s green standards.
D. Similar measures have been taken by other cities such as Cleveland and Denver, but New York’s DHPD is the largest city developer of affordable housing in the country.
E. 45. What is the purpose of describing the boiler room in the first paragraph?
F. To explain the measures the city takes to care for poor people.
G. To suggest that affordable housing is possible in all areas.
H. To show how the environment-friendly building works.
I. To compare old and new boiler rooms.

[单选题]决定受精亲和或不亲和的物质是花粉壁和柱头表面的( )。

A. 蛋白质
B. 硼
C. 钙
D. 硼和钙

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