| straightforward(adjective, simple, plain, natural, genuine) |
| ad-lib(adjective, simple, natural, casual, impulsive) |
| ad lib |
| automatic(adjective, simple, natural, casual, impulsive) |
| childlike(adjective, simple, easy, natural, real) |
| genuine(adjective, open, simple, easy, plain) |
| guileless(adjective, simple, plain, natural, ingenuous) |
| improvised(adjective, simple, natural, casual, impulsive) |
| instinctive(adjective, open, simple, easy, natural) |
| involuntary(adjective, simple, natural, casual, impulsive) |
| plain(adjective, open, smooth, simple, easy) |
| pure(adjective, simple, plain, natural, ingenuous) |
| snap |
| straight(adjective, simple, plain, natural, ingenuous) |
| unarranged |
| unconscious(adjective, simple, natural, casual, impulsive) |
| unforced(adjective, open, simple, easy, natural) |
| unprepared |
| unpretentious(adjective, open, simple, easy, plain) |
| unsophisticated(adjective, open, simple, easy, plain) |