汽车发动机的两大机构是()。
A.曲柄连杆机构和燃料供给机构
B.曲柄连杆机构和润滑机构
C.曲柄连杆机构和冷却机构
D.曲柄连杆机构和配气机构
参考答案:D
儿童看到天上的白云,一会儿看它是“大帽子”;一会儿看它是飘动的“小船”……这种想象属于()。
A.无意想象
B.有意想象
C.再造想象
D.幻想
From facts, scientists have_______ that more energy is being absorbed from the sun, throwing the earth’s energy “out of balance”.
A.confirmed
B.concluded
C.concentrated
D.centered