九地篇 NO.3：
凡为客之道，深入则专。
主人不克，掠于饶野，三军足食;谨养而勿劳，并气积力;运兵计谋，为不可测。
投之无所往，死且不北。死焉不得，士人尽力。兵士甚陷则不惧，无所往则固，深入则拘，不得已则斗。
是故其兵不修而戒，不求而得，不约而亲，不令而信，禁祥去疑，至死无所之。
吾士无余财，非恶货也；无余命，非恶寿也。令发之日，士卒坐者涕沾襟，偃卧者涕交颐，投之无所往，诸、刿之勇也。
这句啥意思：
在敌国境内进行作战的一般规律是：越深入敌国腹地，我军军心就越坚固，敌人就不易战胜我们。
在敌国丰饶地区掠取粮草，部队给养就有了保障。
要注意休整部队，不要使其过于疲劳，保持土气，养精蓄锐。
部署兵力，巧设计谋，使敌人无法判断我军的意图。
将部队置于无路可走的绝境，士卒就会宁死不退。
士卒既能宁死不退，那么他们怎么会不殊死作战呢！
士卒深陷危险的境地，就不再存在恐惧，一旦无路可走，军心就会牢固。
深入敌境军队就不会离散。遇到迫不得已的情况，军队就会殊死奋战。
因此，不须整饬就能注意戒备，不用强求就能完成任务，无须约束就能亲密团结，不待申令就会遵守纪律。
禁止占卜迷信，消除士卒的疑虑，他们至死也不会逃避。
我军士卒没有多余的钱财，并不是不爱钱财；士卒置生死于度外，也不是不想长寿。
当作战命令颁布之时，坐着的士卒泪沾衣襟，躺着的士卒泪流满面，但把士卒置于无路可走的绝境，他们就都会象专诸、曹刿一样的勇敢。
英文这么说：
The following are the principles to be observed by an invading force:
The further you penetrate into a country, the greater will be the solidarity of your troops,and thus the defenders will not prevail against you.
Make forays in fertile country in order to supply your army with food.
Carefully study the well-being of your men,and do not overtax them.
Concentrate your energy and hoard your strength.
Keep your army continually on the move,and devise unfathomable plans.
Throw your soldiers into positions whence there is no escape, and they will prefer death to flight.
If they will face death, there is nothing they may not achieve.
Officers and men alike will put forth their uttermost strength.
Soldiers when in desperate straits lose the sense of fear.
If there is no place of refuge,they will stand firm.
If they are in hostile country,they will show a stubborn front.
If there is no help for it, they will fight hard.
Thus, without waiting to be marshaled, the soldiers will be constantly on the qui vive;
without waiting to be asked, they will do your will; without restrictions,they will be faithful; without giving orders, they can be trusted.
Prohibit the taking of omens, and do away with superstitious doubts. Then, until death itself comes,no calamity need be feared.
If our soldiers are not overburdened with money,it is not because they have a distaste for riches;
if their lives are not unduly long, it is not because they are disinclined to longevity.
On the day they are ordered out to battle,your soldiers may weep, those sitting up bedewing their garments
and those lying down letting the tears run down their cheeks.
But let them once be brought to bay,and they will display the courage of a Chu or a Kuei.
单句理解：
士兵的士气和体力是军队战斗力的根本保证，所以孙子主张用兵作战一定要懂得保持士兵的体力，从而使军队保持旺盛的战斗力。此外用兵要神出鬼没，不要让敌人判断出我军的行动意图，或者推断出我军的行动方向。
