Most villagers agree that horses are far more pleasant _______ than tractors, but they are less efficient.

A．looking at

B．to look at

C．to be looked at

D．being looked at

慢性严重贫血的病儿输血时需要考虑的原则下列哪一项正确（）

A.贫血愈重，每次输血量愈大，速度也愈快

B.贫血愈重，每次输血量愈小，但速度要快

C.贫血愈重，每次输血量愈大，但速度要慢

D.贫血愈重，每次输血量愈小，速度也宜慢

E.贫血愈重，每次输血量愈大，速度不考虑