bi-Xx bicycle; bilingual; by-在旁;副;次要的 bystander; by-product; by-election; by-effect co-共同co- existence; co-operation; co-worker;bi- 双 bicycle; bilingual; by- 在旁；副；次要的 bystander; by-product; by-election; by-effect; co- 共同 co-existence; co-operation; co-worker;