Đồng nghĩa của not know one's arse from one's elbow

incapable incompetent inept inexpert unskilled unfit unqualified unskillful ineffectual inadequate unskilful useless unfitted inapt unable ineffective inexperienced unproficient inferior unequipped pathetic hopeless weak disqualified ineligible poor inefficacious insufficient inproficient unsuited butterfingers naive not equal to no good not equipped to not good enough cack-handed ham-fisted not up to a dead loss not up to scratch not up to snuff lacking ability not much cop leaving much to be desired not up to it unequal to the task out of your depth lacking experience amateurish amateur inefficient untrained bungling unprofessional substandard impotent blundering maladroit wanting deficient powerless unsuitable clumsy floundering worthless unprepared dilettante not cut out for bad feeble unsatisfactory inexpedient undependable unapt dilettantish awkward raw feckless unworkmanlike unequal lousy nonprofessional lacking unsuccessful jackleg unreliable green crude bumbling futile unhandy skill-less incompatible unproductive defective can't hack it ill-equipped cowboy gauche fruitless untaught profitless shoddy slipshod sloppy unpractised bum botched incapacitated lame hapless counterproductive hamstrung duff unschooled bush-league uncultivated inadmissible rotten unpracticed inconvenient limited incommodious not cut out incapable of unqualified for inappropriate unable to do something for toffee untalented incompetent at improper half-baked ill-suited unadvantageous inconsistent not proper edentulous improficient inadept hack shiftless loser talentless toothless insignificant imperfect unstudied faulty bush can't cut it broken flimsy junk ham-handed fumbled heavy-handed slapdash couldn't organize a piss-up in a brewery butterfingered bodged untrained for unable to do something out of one's element can't make the grade all thumbs suboptimal subpar negligent careless not much chop unaccomplished unpolished without finesse not qualified all fingers and thumbs non-qualified no great shakes not prepared undesirable lacking finesse helpless uninitiated unadapted awful appalling atrocious dreadful terrible frightful abysmal dire rubbish pants less capable out to lunch not have it very poor a load of pants unable to do something to save one's life very bad untutored unsuited to inadequate for unfitted for ignorant unversed unacquainted uninformed non-technical not qualified for unchartered uneducated unlicensed uncertificated non-professional new lay found wanting in insufficient for vain pointless unavailing untamed illiterate undisciplined novice nescient wild unprofitable abortive bootless empty idle otiose barren failed nugatory purposeless not trained paltry inutile unfruitful inoperative null unfructuous anticlimactic void indecisive forceless withered defeasible innocuous neutralized neutralised non-successful to no avail to no effect no-go not effective graceless ungainly ungraceful gawky lumbering uncoordinated inelegant klutzy unco clodhopping stumbling oafish gawkish handless like a bull in a china shop cloddish gangling lubberly coarse stiff ponderous clownish left-handed undexterous fumbling rude unrefined shambling uncouth bovine unadept rough flat-footed with two left feet foolish muddled Sunday backyard botching menial avocational unsophisticated artless unacceptable unwieldy second-rate cumbersome heavy-footed wooden having two left feet having two left hands clunky stilted crummy not agile all thumbs insipid unartful sciolistic nonexpert low-skill mutton-fisted unsteady manual labouring fumbly crass hulking loutish lumpish indelicate slouching coltish not professional rough-and-tumble undeveloped laboring bulky rough-hewn two left feet blue-collar ill-bred low-skilled dissatisfactory wretched wrong wack nonspecialist ordinary punk off sour disgraceful abominable deplorable laughable heavy crumby ill execrable miserable lamentable sorry diabolical blunderous elephantine woeful ropy labored laboured pits pitiful God-awful poxy chronic non-specialist egregious not up to par second-class third-rate accident-prone

not know what is going on not know what is happening not know what to say not know when to stop not know where to put yourself not kosher not known when to stop not known not knowing whether one is coming or going not knowing where one's next meal is coming from not knowing when to stop not knowing what to do with oneself