1. when
1.1. summer vacation
1.2. spring vacation
1.3. winter vacation
1.4. weekend
1.5. national holiday
2. information resourse
2.1. trip mazagine
2.2. people
2.2.1. friends
2.2.2. family
2.3. website
2.4. TV show
2.5. newspaper
3. why/what
3.1. traveling/sight seeing
3.1.1. more than 1week
3.1.2. 4days-1week
3.1.3. 1day-3days
3.2. visiting someone
3.2.1. friends
3.2.1.1. 1day-3days
3.2.1.2. 4days-1week
3.2.1.3. more than 1week
3.2.2. relevant
3.2.2.1. more than 1week
3.2.2.2. 4days-1week
3.2.2.3. 1day-3days
3.3. work
3.3.1. few days
3.3.2. few months
3.3.3. more than a year
3.4. school
3.4.1. university dorm
3.5. event
3.5.1. music live
3.5.2. fare
3.5.2.1. fashion
3.6. leisure
3.6.1. movie
3.6.2. theme park
3.6.3. shopping
3.6.4. nature
3.6.4.1. hiking
3.6.4.2. kayakking
3.6.4.3. climbing
4. how much?
4.1. ~$100
4.1.1. food
4.1.2. shopping
4.1.3. souvenir
4.1.4. transportation
4.1.5. leisure (like movie)
4.1.6. sight seeing
4.2. $100~$500
4.2.1. food
4.2.2. shopping
4.2.3. souvenir
4.2.4. transportation
4.2.5. leisure (like movie)
4.2.6. sight seeing
4.3. $500~$1000
4.3.1. food
4.3.2. shopping
4.3.3. souvenir
4.3.4. transportation
4.3.5. leisure (like movie)
4.3.6. sight seeing
4.4. $1000~
4.4.1. food
4.4.2. shopping
4.4.3. souvenir
4.4.4. transportation
4.4.5. leisure (like movie)
4.4.6. sight seeing
5. with whom
5.1. friends
5.1.1. graduation trip
5.1.1.1. high school
5.1.1.2. university
5.1.2. club
5.2. lover
5.2.1. date
5.2.2. honeymoon
5.3. family
5.3.1. family trip
5.3.2. going back home
5.4. school trip
5.4.1. elementary
5.4.2. middle school
5.4.3. high school
5.5. co-wokers
5.5.1. company trip
5.5.2. company club
6. where
6.1. restaurant
6.2. leisure place
6.2.1. shopping nall
6.2.2. theme park
6.2.3. movie