Silent Spring

Multiple-choice exercise

Read the text and choose the correct verb for each numbered apce.

Text

Since the mid-1940s over two hundred basic chemicals (1) been created for use in killing insects, weeds, rodents, and other organisms described in the modern vernacular as 'pests'; and they (2) sold under several thousand different brand names.
These sprays, dusts, and aerosols (3) now applied almost universally to farms, gardens, forests, and homes - non-selective chemicals that (4) the power to kill every insect, the 'good' and the 'bad', to still the song of birds and the leaping of fish in the streams, to coat the leaves with a deadly film, and to linger on in soil - all this though the intended target may be only a few weeds or insects. Can anyone believe it (5) possible to lay down such a barrage of poisons on the surface of the earth without making it unfit for all life? They should not be called 'insecticides', but 'biocides'.
The whole process of spraying (6) caught up in an endless spiral. Since DDT (7) released for civilian use, a process of escalation (8) been going on in which ever more toxic materials must be found. This (9) happened because insects, in a triumphant vindication of Darwin's principle of the survival of the fittest, (10) evolved super races immune to the particular insecticide used, hence a deadlier one (11) always to be developed - and then a deadlier one than that. It (12) happened also because, for reasons to be described later, destructive insects often (13) a 'flareback', or resurgence, after spraying, in numbers greater than before. Thus the chemical war (14) never won, and all life (15) caught in its violent crossfire.

(From Silent Spring by Rachel Carson)