insubstantial

adj 1 not solid or real; imaginary 非实体的; 非实质的; 非实在的; 非真实的; 幻想的: an insubstantial vision, figure, creature 虚幻的景象、 人物、 生物. 2 not firmly or solidly made; weak （做得）不坚固的, 不坚实的, 薄弱的: Early aircraft were insubstantial constructions of wood and glue. 早期的飞行器是木头和胶粘合的脆弱机器. * (fig 比喻) an insubstantial argument, accusation, claim, etc 无真凭实据的争论、 指控、 索赔要求等.

instinct, instinctive, instinctively, institute, institution, institutionalize, instruct, instruction, instructional, instructions, instructive, instructively, instructor, instrument, instrumental, instrumentalist, instrumentality, instrumentation, insubordinate, insubordination, insufferable, insufferably, insufficiency, insufficient, insufficiently, insular, insularity, insulate, insulated, insulating, insulating tape, insulation, insulator, insulin, insult, insulting, insuperable, insuperably, insupportable, insurance,