According to the author, youth hostels are economical and tidy.
____
The bicycle is a relatively recent invention. It is by far the most economical and environmentally friendly mechanical mode of transport yet invented. Describe how the illustrated two-wheeled bicycle below functions, and be sure to mention in your description the machine’s environmentally-friendly feature. You should write at least 120 words.
According to the author, youth hostels are economical and tidy.
____
什么叫经济效益(economical benefit)?理解和运用经济效益概念,应遵循哪些基本原则?经济效益的表示方法有哪些?经济效益计算的基础是什么?
New machines are often more economical than old machines.
大数据的economical(经济性)是讲的数据收集与利用也要讲低成本高收益。
It is more economical to use (), because of their greater strength and longer useful lives.正确答案A