To tell the statement is true or false, we can first use f_add_column() to add more columns to the table.

The added columns should have these data types:
1. Numerical: the numerical strings that can be used in sort, sum
2. Datetype: the strings that describe a date, such as year, month, day
3. String: other strings

/*
col : week | when | kickoff | opponent | results; final score | results; team record | game site | attendance
row 1 : 1 | saturday, april 13 | 7:00 p.m. | at rhein fire | w 27–21 | 1–0 | rheinstadion | 32,092
row 2 : 2 | saturday, april 20 | 7:00 p.m. | london monarchs | w 37–3 | 2–0 | waldstadion | 34,186
row 3 : 3 | sunday, april 28 | 6:00 p.m. | at barcelona dragons | w 33–29 | 3–0 | estadi olímpic de montjuïc | 17,503
*/
Statement: april 20 is the date of the competition with highest attendance.
The existing columns are: "week", "when", "kickoff", "opponent", "results; final score", "results; team record", "game site", "attendance".
Explanation: To tell this statement is true or false, we need to know the attendence number of each competition. We extract the value from column "attendance" and create a different column "attendance number" for each row. The datatype is numerical.
Therefore, the answer is: f_add_column(attendance number). The value: 32092 | 34186 | 17503

/*
col : rank | lane | player | time
row 1 :  | 5 | olga tereshkova (kaz) | 51.86
row 2 :  | 6 | manjeet kaur (ind) | 52.17
row 3 :  | 3 | asami tanno (jpn) | 53.04
*/
Statement: there are one athlete from japan.
The existing columns are: rank, lane, player, time.
Explanation: To tell this statement is true or false, we need to know the country of each athelte. We extract the value from column "player" and create a different column "country of athletes" for each row. The datatype is string.
Therefore, the answer is: f_add_column(country of athletes). The value: kaz | ind | jpn

/*
col : year | competition | venue | position | notes
row 1 : 1991 | european junior championships | thessaloniki, greece | 10th | 4.90 m
row 2 : 1992 | world junior championships | seoul, south korea | 1st | 5.45 m
row 3 : 1996 | european indoor championships | stockholm, sweden | 14th (q) | 5.45 m
*/
Statement: laurens place 1st in 1991.
The existing columns are: year, competition, venue, position, notes.
Explanation: To tell this statement is true or false, we need to know the place of each competition. We extract the value from column "position" and create a different column "placing result" for each row. The datatype is numerical.
Therefore, the answer is: f_add_column(placing result). The value: 10 | 1 | 14

/*
col : iso/iec standard | status | wg
row 1 : iso/iec tr 19759 | published (2005) | 20
row 2 : iso/iec 15288 | published (2008) | 7
row 3 : iso/iec 12207 | published (2008) | 7
*/
Statement: the standards published three times in 2008.
The existing columns are: iso/iec standard, title, status, description, wg.
Explanation: To tell this statement is true or false, we need to know the year of each standard. We extract the value from column "status" and create a different column "year of standard" for each row. The datatype is datetype.
Therefore, the answer is: f_add_column(year of standard). The value: 2005 | 2008 | 2008

/*
col : match | date | ground | opponent | score1 | pos. | pts. | gd
row 1 : 1 | 15 august | a | bayer uerdingen | 3 – 0 | 1 | 2 | 3
row 2 : 2 | 22 july | h | 1. fc kaiserslautern | 1 – 0 | 1 | 4 | 4
row 3 : 4 | 29 september | h | dynamo dresden | 3 – 1 | 1 | 6 | 6
*/
Statement: they play 5 times in august.
The existing columns are: match, date, ground, opponent, score1, pos., pts., gd.
Explanation: To tell this statement is true or false, we need to know the month of each match. We extract the value from column "date" and create a different column "month" for each row. The datatype is datetype.
Therefore, the answer is: f_add_column(month). The value: august | july | september

/*
table caption : 1984 u.s. open (golf)
col : place | player | country | score | to par
row 1 : 1 | hale irwin | united states | 68 + 68 = 136 | - 4
row 2 : 2 | fuzzy zoeller | united states | 71 + 66 = 137 | -- 3
row 3 : t3 | david canipe | united states | 69 + 69 = 138 | - 2
*/
Statement: david canipe of united states has 138 score
The existing columns are: place, player, country, score, to par.
Explanation: To tell this statement is true or false, we need to know the score values of each player. We extract the value from column "score" and create a different column "score value" for each row. The datatype is numerical.
Therefore, the answer is: f_add_column(score value). The value: 136 | 137 | 138

/*
col : code | county | former province | area (km2) | population; census 2009 | capital
row 1 : 1 | mombasa | coast | 212.5 | 939,370 | mombasa (city)
row 2 : 2 | kwale | coast | 8,270.3 | 649,931 | kwale
row 3 : 3 | kilifi | coast | 12,245.9 | 1,109,735 | kilifi
*/
Statement: kwale has a population in 2009 higher than 500,000.
The existing columns are: code, county, former province, area (km2), population; census 2009, capital.
Explanation: To tell this statement is true or false, we need to know the population of each county. We extract the value from column "population; census 2009" and create a different column "population" for each row. The datatype is numerical.
Therefore, the answer is: f_add_column(population). The value: 939370 | 649311 | 1109735