41-50组
41不可推卸的义务
an indispensable duty
42满足需求
satisfy/ meet the needs / requirements of...
43宝贵的自然资源
valuable natural resources
44方便快捷
convenient and efficient
45在人类生活的方方面面
in all aspects of human life
46社会进步的体现
a symbol of society progress
47科技的飞速更新
the accelerated updating of science technology
48有/提供如下理由/证据
have/ provide the following reasons/ evidence
49在一定程度上
to some extent/degree / in some way
50理论和实践相结合
integrate theory with practice / apply theory to practice