For each blank select one entry from the corresponding column of choices. Fill all blanks in the way that best completes the text.

The Wankel rotary engine was an engineering marvel that (i) automobile exhaust emissions, but because it was less fuel efficient than the standard piston-cylinder engine, it was (ii) in the early 1970s when (iii) pollution gave way to panic over fuel shortages.

Blank (i)

depended totally on

preceded the problems with

substantially reduced

Blank (ii)

necessitated

conceived

abandoned

Blank (iii)

ignorance of

espousal of

preoccupation with

我的答案： 无