填空题 Questions21 and22
Choose TWO letters, A-E.
Which TWO possible objections to a roof garden are discussed?
A. problems of access
B. the cost of construction
C. the time needed to install it
D. who will look after it
E. how to support the weight of it
Questions 23 and 24
Choose TWO letters, A-E.
Which TWO recent developments in roof-garden building are mentioned?
A. waterproof barrier materials
B. drainage systems
C. tank designs
D. lightweight construction materials
E. watering systems