en_tn_lite_do_not_use/isa/19/08.md

The fishermen will wail and mourn, and all who cast a hook into the Nile will mourn, and those who spread nets on the waters will waste away

These three phrases mean basically the same thing. If necessary, the reason they will grieve can be stated clearly. Alternate translation: "The fishermen who catch fish with hooks or nets will cry in despair because the fish in the Nile have died" (See: rc://en/ta/man/jit/figs-explicit and rc://en/ta/man/jit/figs-parallelism)

cast a hook into the Nile

In order to catch fish, some people put a little food on a hook, tie the hook to a string, and throw the hook into the water. When a fish tries to eat the food, its mouth gets stuck on the hook, and the person pulls the fish out of the water. (See: rc://en/ta/man/jit/translate-unknown)

cast

throw

spread nets on the waters

In order to catch fish, some people toss a net on the water. When fish get caught in it, they pull the net with the fish out of the water. (See: rc://en/ta/man/jit/translate-unknown)

will waste away

"will grieve." This weakness probably comes from grief.