The wheel is the simplest yet perhaps the most unusual of all inventions, because there are no wheels in nature. No living thing was ever born with wheels.
举一反三
- The wheel is the simplest yet the most remarkable of all inventions, because there are no wheels in nature -- no living thing was ever created with wheels. A: 轮子是一切发明中最简单也是最不起眼的，因为不存在天然的轮子——没有一种生物是生来就有轮子的。 B: 轮子是一切发明中最简便却最完美的，因为自然界不存在轮子——没有一种生物是生来就会用轮子的。 C: 轮子是一切发明中最简单却又最了不起的发明，因为自然界不存在轮子——没有一种生物是用轮子创造出来的。 D: 轮子是一切发明中最简单，然而最了不起的发明，因为没有自然的轮子——即使有也不能用轮子创造出生物来的。
- The plane succeeded in carrying the boy on board with ______ in the air.A. one wheel C. three wheelsB. two wheels D. four wheels A: two wheels B: four wheels C: three wheels D: The plane succeeded in carrying the boy on board with ______ in the air. E: one wheel
- The plane succeeded in carrying the boy on board with ______ in the air. A: one wheel B: two wheels C: three wheels D: four wheels
- The prismatic transmission shaft is shown in the figure. Wheels B and D are driving wheels and wheels A, C ,E are driven wheels. If the input powers on driving wheels B and D are equal, the output powers on driven wheels A, C and E are equal too, and if only torsional deformation is considered and bending deformation is not considered, the position of dangerous section is ( ).[img=385x158]1803a368564fb94.png[/img] A: Only in segment AB; B: In segment BC; C: In segment CD; D: In segment AB and segment DE.
- A set of are installed to control the speed and direction of the vehicle. A: wheels B: gears C: gea D: wheel