what's the meaning?there's sth wrong!
Hello,boy!(maybeyouareagirl,ifthatso,Iamaskingyouforexcuse)Iwanttotellyou,don'tmakeafanwithyourself.YoumustknowwhydoyoustudyEnglish.It'notforcheating,notforshowoff.It'sonlyatoolforyourself.SoIhopeyoutostudyitharder,don'tworryaboutyourlevel.Pleas ,stepbystep,thenyou'llgetabigprogress,thenyoucanwriteanything.That'sall!
Hello!Thank you for your letter.I have looked your family photo.You are very lovely.
15JobbySteetLondonNW2Englan !Thankyouforyourletter.Ihavelookedyourfamilyphoto.Youareverylovely.WhatisLondon'sweather?Cold?Hot?InmycityWeifang,it'snerycoldnow.Yesterdaytherewasasnow.Oh,howbeautiful.Doyoulikesnow?Doyoulikewinter?Ilikethemverymuchbecausetherarebeautiful.Andyou?Bestwishes!Yours,Daisy
问：为什么y=tan<pai/2>-cos<pai/2>的周期为pai在上<0,pai/2>递增
答：请问这个是函数吗？详情>>
答：详情>>
