LindaandDavidhavetraveledbyairfromLondontoSydney,Austra...
问题详情：LindaandDavidhavetraveledbyairfromLondontoSydney,Australia．Lindahaspromised（答应）hermotherthatshewillringhertoletherknowthattheyhavearrivedsafely．Thisissomethingshehaddoneeversinceshewasachild．Davi...