【推荐1】As he________(injure) his leg before, he had to quit the game. （所给词的适当形式填空）

【推荐2】At least 270 people _________(injure) because of the underground gas explosions in southern Taiwan. (所给词的适当形式填空)

【推荐3】He managed to finish the marathon although he_______ (injure) his ankle before the race. (所给词的适当形式填空)

【推荐1】"Where did she come from?" asked an astonished sprinting world, before______(conclude) that she must be one of those one-hit wonders that spring up from time to time, only to disappear again without signs. (所给词的适当形式填空)

【推荐2】We don’t allow ________ (park) here unless you have a permit. （所给词的适当形式填空）

【推荐3】It is well worth ________（make）an effort to promote the public awareness of environmental protection. （所给词的适当形式填空）