第1题
A.Interuteric crest
B.Left ureteric orifice
C.Right ureteric orifice
D.Urachus
E.Urethral orifice
第2题
Sharks can stop themselves from sinking because ______.
A.their dorsal fins are very valuable
B.they have a swim bladder
C.they have fins for swimming
D.they have skeletons made of cartilage
第5题
The sun's heat______.
A.makes the air move
B.makes the air still
C.makes the air cold
D.reflects back into space
第6题
B.By planes
C.In planes
D.By air
第9题
In the following air pollutants, ______ are the Secondary pollutants.
A.O3B.SO3C.NO2D.SO2E.NO
第10题
How will the government know what the air quality is?
A.The factories will test the air every day.
B.Scientists will test it every day.
C.A report will be published.
D.They will ask homeowners