16.Colours 17.students\’ 18.hungry 19 relaxed 20 Hard
Many scientists find that colors can change people\’s feelings.It\’s very interesting.Now this knowledge is used in many places.For example，classroom walls are usually painted green because green makes students feel relaxed.It is also good for the students eyes.Some books are also green or light blue for the same reason.Restaurant owners have to know not only how to make food，but also how to make money.Here are some things they\’ve learned from scientific studies.The color red makes people hungry.Many fast food restaurants have red tables or walls.Soft colors like pink and light blue make people feel relaxed，so they spend more time eating.Loud music may be nice at first，but it soon makes people want to leave.Hard seats also make people want to eat quickly and leave.Many restaurants，especially fast food restaurants use this knowledge to make people eat faster.

16.Colours 17.students\’ 18.hungry 19 relaxed 20 Hard
Many scientists find that colors can change people\’s feelings.It\’s very interesting.Now this knowledge is used in many places.For example，classroom walls are usually painted green because green makes students feel relaxed.It is also good for the students eyes.Some books are also green or light blue for the same reason.Restaurant owners have to know not only how to make food，but also how to make money.Here are some things they\’ve learned from scientific studies.The color red makes people hungry.Many fast food restaurants have red tables or walls.Soft colors like pink and light blue make people feel relaxed，so they spend more time eating.Loud music may be nice at first，but it soon makes people want to leave.Hard seats also make people want to eat quickly and leave.Many restaurants，especially fast food restaurants use this knowledge to make people eat faster.