If you are writing or studying, it makes much difference where the light comes from. People use  36  and pens every day. They have to be very careful about the  37   of the light because the light shines on their work.
Every  38  gets its light either from daylight  39  the window or from the lamps,   40   no matter what kind of light it is, the way it shines is very important to the eyes.
Take a book and sit with your  41  towards the window, and try to read. Your shadow(影子) falls all over the page and makes it  4  for your eyes as if you were in a  43  room. Now turn around and face the window. The page is in shadow again,  44  the bright light is in your eyes.Try sitting with your  45  side towards the window. This is very good for reading, but if you were writing, the shadow  46   fall across the page and trouble you  47  .There is another way – sit  48  your left side to the window. Now everything is perfect for  49    as well.
Whatever kind of light is in the room, the rule about the right way to sit is  50  the same. So you see different ways to sit make much difference in writing or studying.
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A．eyes B．heads C．books D．hands

A．road B．path C．way D．trail

A．house B．woman C．man D．animal

A．from B．through C．into D．inside

A．but B．until C．if D．when

A．side B．back C．body D．front

A．good B．bad C．useful D．clear

A．bright B．clean C．dirty D．dark

A．while B．or C．if D．till

A．front B．back C．left D．right

A．can B．may C．has to D．ought to

A．few B．a few C．little D．a little

A．by B．with C．against D．near

A．speaking B．reading C．writing D．playing

A．only B．never C．hardly D．always