1：Wouldyoubefreetocomebythen?We’llhavethemworkedoutbythisevening.我在应用时就会忘记用by,是不是一定要加by?2：Pleasekeepusinformedofthelatestquotationforthefollowingitems.这个句子的结构我有点

　　1：Wouldyoubefreetocomebythen?　We’llhavethemworkedoutbythisevening.我在应用时就会忘记用by,是不是一定要加by?

　　2：Pleasekeepusinformedofthelatestquotationforthefollowingitems.这个句子的结构我有点糊涂,主要是us后面的informedofthelatestquotation,翻字典,keep与inform联系不上,就是没有词组一类的联系,这里keep应该是谓语动词吧,应该怎么解释才正确呢?

　　3：itisusefultostudyenglish.studyingenglishisuseful.itisusefulstudyingenglish.这三个小短句是表示同样语气吗?

　　4：学到一篇小短文,其中有一段：forolderpeopletomovesouthtotheseplaceswhentheyretire.Typicallythesepeopleselltheirhousesintheirhomecommunitiesandmovesouthtobeginanewlifeasseniorcitizens.Theirchildrenlikelyhavehomesoftheirown,andmanyofthemaremovingsouthawayfromcommunitieswheretheywereraised.这里感觉theirchildrenlikelyhavehomesoftheirown始终找不到合适的解释,甚至多余,当然这是不可能.我只能理解到manyoftheirchildrenaremovingsouth.

　　祝老师身体健康,生活幸福!