rudimentary

This class requires a rudimentary knowledge of human anatomy.这门课要求具备人体解剖学的基本知识。

He speaks rudimentary English.他会讲简单的英语。

rudimentary technology不成熟的技术

When baseball was in its rudimentary stages, different teams played by different rules.棒球运动发展早期，不同的球队按照不同的规则进行比赛。

Some insects have only rudimentary wings.有些昆虫的翅膀已退化。