Question 959822
This is not a website for English tutoring, but let's see if I can help you. (For the future, this is a MATH help website, and math only.)
I will write the correct sentences below:

1)Overcrowding of and within houses is an unhealthy factor which favors the spread of many diseases.
~
2) Every person at one time or another is called upon to make a decision, but making a decision is one of the hardest jobs which one has to do.
~
3) We were touched by his generosity when he obviously could ill afford to be so generous.
~
4) When office workers take part in planning work details, their feelings of having status rise.
~
5) Please feel free to call upon our office if we can be of further service to you.
~
6) A plan to build more medical centers in major parts of the country has been revealed yesterday.
~
7) He would have played much better today if he had not sprained his ankle during the semi-final match two days ago.
~
8) The telephone rang continuously for two minutes, fell silent, and then sounded of five short rings.
~
9) After the game, the coach complimented those players who showed bravery during the crucial game.
~
10) There is no doubt whether the decision of the Council was influenced by politics.
~
11) Several Senators and congressmen were absent in the committee meetings most of the time.
~
12) Learners set goals as motivation for learning, and their successes of failures in achieving these goals determine how they set their future goals.
~
13) We were discussing political issues, so her remarks about clothes and fashion were completely besides the point.
~
14) A systematic plan for handling the mail helped speed up the performance of office work.
~
15) When a soldier completes his military service, he is usually glad to get into civilian clothes again.
~
16) The director wanted to know how many employees had been assigned to conduct the examination.
~
17) Now is the time to talk about the floods and to implement flood control projects before the rainy season sets in.
~
18) Many advocates for women in development emphasize the need for greater equality between men and women.
~
19) It is likely that you may be one of the many people who need to communicate better.
~
20) Overcrowding of and within houses is an unhealthy factor which favors the spread of many diseases.
~
21) With regards to the terrorism problem, the President said that the Cabinet and the Military were closely monitoring the activities of the foreign nationals.
~
22) "All is not lost when hope lingers," the mother said to her son, who was inflicted with pain.
~
23) In other countries, there is a strong trend in favor of learning and part-time programs.
~
24) The poor and unfortunate children have gone home, haven't they?
~
25) The Labor Secretary will meet representatives of the entertainment industry tomorrow to discuss problems affecting the working conditions of the Chinese workers abroad.