If you travel, try to avoid riding a bicycle.
如果出行尽量避免骑自行车。
Riding a bicycle again? How long will you insist?
又在骑单车啦?要坚持多久啊?。
This time he had no truck; he was riding a bicycle!
这回他没有开车，而是骑着辆自行车！
She had her foot hurt while riding a bicycle yesterday.
昨天在骑自行车的时候她的.脚受伤了。
When did you see him riding a bicycle on the playground?
你何时看到他在操场上骑自行车的？