THESAURUS
take on
accept, ache, acquire, add, admit, adopt, agonize, air a grievance, annex, antagonize, append, appropriate, assume, attack, attempt, battle, be livid, be pissed, beat against, beat up against, beef, bellyache, bespeak, bitch, bleed, bluster, boil, book, breast the wave, brief, brood over, browned off, buck, buckle to, buffet, buffet the waves, burn, carry on, chafe, clamor, close with, combat, come by, come in for, compete with, complain, conduct, contend against, contest, copy, crab, croak, derive, derive from, dive into, do, do battle, drag down, draw, draw from, embark in, embark upon, employ, endeavor, engage, engage in, engage in battle, enter on, enter upon, exercise, fall into, fall to, fight, fight against, follow, fret, fret and fume, fume, fuss, gain, get, get busy, get cracking, get going, get under way, get with it, give a fling, give a go, give a try, give a whirl, give battle, go about, go at, go in for, go into, go on, go to it, go upon, grapple with, grieve, gripe, groan, grouch, grouse, growl, grumble, grunt, have, have a conniption, have at, have coming in, hire, holler, hop to it, howl, imitate, infringe, join battle, join battle with, join issue, jump to it, kick, labor against, launch forth, launch into, lay about, light into, lodge a complaint, make a try, make use of, militate against, mock, mope, mourn, move into, murmur, mutter, obtain, offer resistance, pine, pine away, pirate, pissed off, pitch in, pitch into, plagiarize, plunge into, practice, preengage, proceed to, prosecute, pull, pull down, pursue, put on, rage, raise Cain, raise a howl, raise hell, raise the devil, raise the roof, rant, rant and rave, rave, receive, recruit, register a complaint, reluct, reluctate, reserve, retain, rival, sail into, secure, seethe, set about, set at, set forward, set going, set to, set to work, sign on, sign up, sign up for, simmer, simulate, sizzle, smoke, smolder, sorrow, specialize in, squawk, start in, steal, stem the tide, stew, storm, strike, strive against, struggle against, subjoin, superadd, tackle, take, take in, take into employment, take over, take to, take up, throw a fit, try conclusions, turn to, undertake, use, venture upon, vie with, wade into, wage, work at, worry, yap, yelp
ROGET THESAURUS
take on
Pain
VB
feel pain, suffer pain, experience pain, undergo pain, bear pain, endure pain, smart, ache, suffer, bleed, ail, be the victim of, labor under afflictions, bear the cross, quaff the bitter cup, have a bad time of it, fall on evil days, go hard with, come to grief, fall a sacrifice to, drain the cup of misery to the dregs, sup full of horrors, sit on thorns, be on pins and needles, wince, fret, chafe, worry oneself, be in a taking, fret and fume,
take on, take to heart, cark, grieve, mourn, yearn, repine, pine, droop, languish, sink, give way, despair, break one's heart, weigh upon the heart.
Discontent
VB
be discontented, quarrel with one's bread and butter, repine, regret, wish one at the bottom of the Red Sea,
take on, take to heart, shrug the shoulders, make a wry face, pull a long face, knit one's brows, look blue, look black, look black as thunder, look blank, look glum, take in bad part, take ill, fret, chafe, make a piece of work, grumble, croak, lament, cause discontent, dissatisfy, disappoint, mortify, put out, disconcert, cut up, dishearten.
Dejection
VB
be dejected, grieve, mourn,
take on, give way, lose heart, despond, droop, sink, lower, look downcast, frown, pout, hang down the head, pull a long face, make a long face, laugh on the wrong side of the mouth, grin a ghastly smile, look blue, look like a drowned man, lay to heart, take to heart, mope, brood over, fret, sulk, pine, pine away, yearn, repine, despair, refrain from laughter, keep one's countenance, be grave, look grave, repress a smile, depress, discourage, dishearten, dispirit, damp, dull, deject, lower, sink, dash, knock down, unman, prostrate, break one's heart, frown upon, cast a gloom, cast a shade on, sadden, damp one's hopes, dash one's hopes, wither one's hopes, weigh on the mind, lie heavy on the mind, prey on the mind, weigh on the spirits, lie heavy on the spirits, prey on the spirits, damp the spirits, depress the spirits.
