蔡徐Don't wait. The time will never be just right.

凭啥The snowstorm causes schools and businesses to close for the day.​蔡徐You study physics to understand how the universe works.​

凭啥They travel by airplane to attend an international conference.​蔡徐I listen to the radio while driving to work each day.​凭啥The fire provides light for us to see during the power outage.​

蔡徐We play volleyball on the beach during our summer vacation.​凭啥A fish swims upstream to spawn in the same place it was born.​

蔡徐He jumps over the hurdle during the track and field competition.​

凭啥She teaches computer skills to senior citizens at the community center.​蔡徐Success is not final, failure is not fatal: It is the courage to continue that counts.

凭啥Great things never come from comfort zones.蔡徐Great things never come from comfort zones.

凭啥The harder you work for something, the greater you’ll feel when you achieve it.蔡徐The way to get started is to quit talking and begin doing.

(责任编辑：杨雪帆)