| massive(adjective, hard, difficult, heavy, complex) |
| weighty(adjective, hard, difficult, big, heavy) |
| heavy(adjective, dull, quiet, easy, severe) |
| leaden(adjective, hard, difficult, heavy, complex) |
| hefty(adjective, hard, great, difficult, big) |
| stodgy(adjective, dull, hard, difficult, complex) |
| laborious(adjective, hard, difficult, heavy, complex) |
| burdensome(adjective, hard, difficult, heavy, complex) |
| lumpish(adjective, hard, easy, difficult, heavy) |
| sluggish(adjective, dull, hard, difficult, complex) |
| heavy-handed(adjective, good, dull, hard, difficult) |
| oppressive(adjective, hard, difficult, heavy, complex) |
| plodding(adjective, hard, difficult, complex, tedious) |
| grave(adjective, hard, difficult, gloomy, complex) |
| massy(adjective, hard, difficult, complex) |
| hard(adjective, difficult, complex) |
| lumpy(adjective, hard, easy, difficult, heavy) |
| heavyweight(adjective, hard, difficult, heavy, complex) |
| arduous(adjective, hard, difficult, complex) |
| elaborate(adjective, hard, difficult, complex) |