(1) Except for scientific acknowledgement of wt's existence, litle attention (o) was paid to
uranium (ountil the end of the nineteenth century.
(2) Sprinkling salt on icy roads (ohave proved to be an inexpensive and effective method of
keeping roads (oSafe ajin winter.
(3) aAs for the effectiveness of advertisements, for years psychology ohas been able to identify (oa
number of reliable techniques that (a)encourage people buy various products.
(4) (Although the department store (b)was crowded with (oa lot of customers, she bought (ymany
furnitures.
(5) (aThe starting.point for selling a product w)WOuld seem to (obe convinced people that they want
1t, or, (aeven better, that they need it.