Labor, exert.
Endeavour
I've is a word that means I have. I'll is a word that means I will.
Pester is a six letter word that means to annoy
laurel, usurer, neural, neuron, course, plural, source, sturdy
little, kettle, mettle, cattle, rattle, tattle, saddle, waddle
It means applied, or used, as in to put forth an effort, e.g. He exerted a lot of energy to reach the summit. The word (noun "exertion") has the connotation of being a "strenuous" effort.
Evolve, Evoke, Educe, extract
A fifteen-letter word that means difficult is "challenging." It describes something that poses a significant test or difficulty, often requiring considerable effort or skill to overcome.
trait
The four-letter word for receiving payment for your work is "earn." It signifies the process of obtaining compensation or reward in exchange for services rendered or effort put forth.
I am anxious to hear the explanation you are about to put forth. Please put forth your left foot.
adverseassertsbisectscamerascarefulcavemandiversedeceivedependsdesertsdeservefireflyfiremanforeverforestsforeseefreedomgrievesinfestsingestsimmenseinsectsintegerintendsintensemomentsobserveparentsreceivereleaserepealsresealsresentsrevealsreverseshieldssomedaysomewaysomeonestretchtalents
U is the second letter in the word quarter.
"Oscillate" means to move back and forth in a regular rhythm.
The word is 'cinch'.
trudge
U