下列划线成语使用不正确的一项是（ ）

Dave has ________ the company since his father retired.

Li Feng’s __________ of devotion to otherswill be remembered not only in Chinabut also in some other parts of the world.

only too ready to help others, seldom, ______,refusing them when they turn to him.

How about paying a visit to Mr. Richardson, our former history teacher?—Good idea. I will e-mail him today so he ___ know ___ to expect us.