几道英语语法 关于动词

几道英语语法 关于动词1.The company will ____chain stores to expand their business.A.set up B.set off C.set out D.put on2.If the dog___,we don't mind whether it____.A.smells good; smells badly B.smells well; smelt badC.smelt badly; smells good D.smells well; smells good3.New laws have been made to stop cars or motorbikes from____ out dirty smoke into the air.A.turning B.letting C.throwing D.making正确答案是B,为什么?