OZONE IS AN UNSTABLE (A) , FAINTLY BLUISH GAS THAT IS (B) THE MOST...

55.Ozone is an unstable (A) , faintly bluish gas that is (B) the most chemical (C)

active form of (D) oxygen.

Insert a preposition in each gap to complete the following passage.

According to some scientists, high-risk sports can be valuable (56)___________ certain

types of people. Such activities help them learn that being frightened doesn’t mean that

they have to lose control. The recent fashion (57)_____________ jumping from bridges

attached (58)_______ a length of elastic rope, known as “bungee jumping”, has now been

tried (59)________ millions of people over the world, and interest (60)____ it is

continuing to grow. Before the special elastic rope is tightened (61)________ them,

jumpers reach speeds of nearly 160 kph. First-timers are usually too terrified to open their

mouths, and when they are finally lowered safely (62)_________ the ground, they walk

around with broad smiles (63)_________ their faces, saying repeatedly how amazing it

was. However, for some people, it is only the embarrassment of refusing to jump

(64)_____ the last minute that finally persuades them to conquer the fear of heights and

push them off (65)_____ space.

Complete each of the following sentences in such a way that it means exactly the

same as the sentence before it.