57. A．set

B．left

C．headed

D. backed

56. A．longer

B．shorter

C．later

D. sooner

55. A．falling

B．touching

C．finding

D. feeling

54. A．heavy

B．weightless

C．huge

D. tiny

53. A．joy

B．surprise

C．tension

D. trouble

52. A．ears

B．fingers

C．eyes

D. cheeks

51. A．released

B．caught

C．trapped

D. fastened

50. A．refused

B．agreed

C．promised

D. allowed

49. A．washed up

B．washed over

C．washed away

D. washed down

48. A．car

B．river

C．place

D. pool