Psychologically there are two dangers to be guarded against in
old age. One of these is due absorption in the past. It does not __1__
work to live in memories, in regrets for the good old days, or in __2__
sadness about friends who are dead. One's thoughts must be directed
to the future, and to things which there is something to be done. __3__
This is not always easy; one's own past is a gradually increasing
weight. It is easy to think for oneself that ont's emotions __4__
are used to be more vivid than they are, and one's mind more __5__
keen. If this is true it should be forgotten, and if it is forgotten it
will probably not be true.
The other thing to be avoided is clinging to youth in hope of __6__
sucking vigour from its vitality. When your children are growing up __7__
they want to live their own lives, and if you continue to be as
interested in them as you were when they were young, you are likely to
become a burden to them, except they are unusually callous. I do not __8__
mean that one should be without interest in them, but one's interest
should be contemplatory and, if possible, philanthropic, but not __9__
unduly emotional. Animals become indifferent to their young as soon
as their young can look after themselves, but human beings, owing
to the length of infantry, find this difficult. __10__

答案及解析:
1.due-undue
如果是due absoption，就沒有必要說two dangers to guarded against，所以這里犯了語義顛倒的錯誤。
2.work-do
work在這里用得不好，應該為do，表示“能……”，work往往表示“行不行得通”，如：It does not work to employ two people. We need at least 5.
3.^which-about
這里缺少了介詞about，使先行詞things 和something to be done無法連接。
4.for-to
to think for oneself表示“為自己著想”，這這里顯然不是這個意思，應改為to oneself 表示“自己想……”，類似于to say to oneself。
5.are（used）-/
be used to 表示“習慣于……”，而這里的意思是“過去曾經(jīng)……”，所以應改為used to do。
6.^hope-the
詞組in the hope of 或 in hopes of 表示“懷著……的希望”。
7.growing-grown
be growing up 表示“在成長的過程中”，而這里表示的是“當孩子們長大以后……”，所以應改為are grown up。
8.except-unless
except表示“除了……之外”，在意思上不貼切，應改為unless表示“除非……”。
9.contemplatory-contemplative
沒有contemplatory這個詞，有的是contemplative，表示“沉思的，冥想的”
10.infantry-infancy
infantry表示“步兵，步兵團”，應該為infancy，表示“幼年”。