Rudimentary

/ˌruːdɪˈmɛntəri/ adjective easy

Basic, undeveloped, or existing only in an early, simple form.

His rudimentary grasp of Spanish let him order food but not hold a real conversation.

Memory Trick

Rudimentary comes from 'rudiment,' the first crude sketch of something -- a rudimentary skill is still stuck at that rough, unfinished draft stage.