1：I will dedicate the book to the child from whom this grown

1：I will dedicate the book to the child from whom this grown-up grew.这句话从后半部分怎么看不懂（from whom this grown-up grew）
2：They always need to have things explained.(为什么多出个have things).
3：The grown-ups' response,this time,was to advise me to lay aside my drawings of boa constrictors,whether from the inside or the outside,and devote myself instead to geography,history,arithmetic and grammar.(instead为什么在那里).
4：In the course of this life I have had a great many encounters with a great many people who have been concerned with matters of consequence（have been concerned with matters of consequence这段话怎么翻译好）.
5：Whenever I met one of them who seemed to me at all clear-sighted（at all 有什么用）.

英文小说中的语言翻译时要结合语境,既要准确,又要符合中国人习惯.
1：I will dedicate the book to the child from whom this grown-up grew.我愿意把这本书献给儿童时代的这个大人.
知道grow from是“由...长大; 由...发展起来”就行了.“这些大人是从儿时成长起来的”.但这句话中心词是child,所以也可翻成“这个大人小的时候”.
2：They always need to have things explained.他们总是需要（别人作出）解释.
have sth done直译就是“使某事被做”.比如：have the machine repaired.修理这台机器.
比较一下：“They always need to explain these things”,他们需要对这些事情作出解释.
原句要表达的是“他们总是需要一些事情被别人解释”的意思.
3：The grown-ups' response,this time,was to advise me to lay aside my drawings of boa constrictors,whether from the inside or the outside,and devote myself instead to geography,history,arithmetic and grammar.大人们劝我把这些画着开着肚皮的,或闭上肚皮的蟒蛇的图画放在一边,还是把兴趣放在地理、历史、算术、语法上.
英文中的副词的位置比较灵活.instead一般放在句首或句尾,但一定要在介词of、for、to的前面.
如这句：yearned instead for a home and family.宁可期待有一个家和家庭.
4：In the course of this life I have had a great many encounters with a great many people who have been concerned with matters of consequence 在我的一生中,跟许多(只)关心大事（干大事）的人有过很多的接触.
be concerned with表示“对……感兴趣,参与,干涉”
consequence还有“重要”的意思,of consequence表示“有势力的、重要的”,如a person of consequence,举足轻重的人
因此,people who have been concerned with matters of consequence直译就是“关心大事的人”或者说是“参与干大事的人”,要根据上下文确定.
5：Whenever I met one of them who seemed to me at all clear-sighted 当我遇到一个头脑（在我）看来似乎很聪明的大人时
at all 指“根本、纯粹” ,因为前面有seem,所以at all在这里有讽刺意味,含有实质上并非如此的意思.
感觉通篇都在讽刺这些grown-up.