unable to be stopped or changed, unstoppable

pay attention to, listen to

proof, sth that shows there is reason to believe sth is true

varied, composed of different kinds

look like, be similar to

make sure of, make sure that

great effort made to overcome a difficulty

succeed in reaching sth (e.g., a goal) through hard work or strong effort

important new step or discovery

lack of sth that is necessary

have an influence on

change, become or make sth/sb become different

give variety to sth, usually by expanding or adding to sb’s/sth’s skills, interests, or holdings

that can bend or be bent easily

a clear and firm request

in the end, after some time has passed

an act of cutting open part of a person or animal’s body to remove or repair sth that is damaged; a surgical procedure

force sth to rise or increase

strong feeling of wanting

cause to feel admiration or respect

study by looking over notes and course material

annoy or bother sb to an extreme degree

force sb to close down a business